Surgical tool systems, and methods of use thereof

ABSTRACT

Surgical tool systems and methods of use thereof for performing endoscopic surgical procedures, which systems include a handpiece and a surgical accessory which detachably connects to the handpiece. The surgical accessory has a distal end which defines a cutting head incorporating two different types of tissue-treating areas.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Application Ser.No. 62/540,303 filed on Aug. 2, 2017, which is hereby incorporated byreference in its entirety herein.

TECHNICAL FIELD

This disclosure generally relates to surgical tool systems and methodsfor performing endoscopic surgical procedures and, more particularly, totool systems and methods utilizing a surgical accessory whichincorporates a cutting head configuration optimized for removing bothsoft and hard tissue.

BACKGROUND

Endoscopic surgical procedures are routinely performed in order toaccomplish various surgical tasks. In such a surgical procedure, smallincisions or portals are made in the patient. An endoscope, which is adevice that allows medical personnel to view the surgical site, isinserted in one of the portals and surgical instruments used to performother tasks are inserted into other portals. The surgeon views thesurgical site through the endoscope to determine how to manipulate thesurgical instruments in order to accomplish the desired procedure. Anadvantage of performing endoscopic surgery is that, since the portionsof the body that are cut open are minimized, the portions of the bodythat need to heal after the surgery are likewise reduced. Moreover,during an endoscopic surgical procedure, only relatively small portionsof the internal organs and tissue are exposed to the open environment.This minimal opening of the body lessens the extent to which the organsand tissue are open to infection.

The ability to perform endoscopic surgery is enhanced by the developmentof powered surgical tool systems especially designed to perform suchprocedures. One such exemplary tool system is sold by the assigneehereof under the trademark FORMULA®. This tool system includes ahandpiece designed to be held in the hand of the surgeon. The handpiecehas a front or distal end provided with a coupling assembly forreleasably holding a surgical accessory, and a motor disposed within ahandpiece housing which drives the accessory. The surgical accessories,such as shavers, drills and burs, include a hub which defines theproximal end of the accessory and is appropriately configured tocooperate with the coupling assembly of the handpiece to lock theaccessory thereto. Such accessories also include an elongated andtubular outer housing element having a proximal end fixed to the hub,and an elongated cutting element including a drive shaft disposed withinthe housing element. When the accessory is attached to the handpiece,the handpiece motor couples to the drive shaft of the accessory andmoves same relative to the outer housing element. The handpiece motor isselectively actuable to drive the accessory drive shaft so as to cause adesired cutting action at the distal end of the accessory. The handpieceis associated with a control unit which controls the functioningthereof, and is actuated by the user via appropriate buttons provided onthe handpiece itself, at the control unit or through use of afootswitch.

Mechanical surgical accessories, such as the shaver, drill and burdiscussed above, are commonly used in arthroscopic procedures, and allowfor the resection of hard and soft bodily tissues, for example, thosefound within the knee, shoulder and other joints. This type of surgicalaccessory may be utilized for both soft and hard tissue removal. In ashaver-type surgical accessory, the outer housing element incorporates awindow or opening at the distal end, which window is defined by an edgeof the wall of the outer housing element. The cutting element driveshaft at the distal end thereof includes a cutting head having a windowdefined by an edge of the wall of the cutting head. These window edgesof the housing and cutting elements are configured to cut tissue, andwhen the cutting element is disposed within the housing element, thecutting head window is positioned adjacent the window of the housingelement. As the drive shaft is moved relative to the housing element bythe handpiece motor, the cutting edge of the cutting head window and theopposed and facing cutting edge of the housing element window cause acutting or scissoring action which effectively severs tissue locatedwithin the housing element window and between the opposed cutting edgesof the housing element and the cutting head. The configurations of theseopposed edges allow for removal of particular tissue types, and avariety of different cutting window geometries are available tospecifically address the type of cutting the accessory is to carry outor in accordance with the particular preference of the surgeon. In thisregard, the windows of both of the housing element and the cutting headmay be provided with straight cutting edges which may be useful formaking fine or detailed cuts, and may also be used for removing areas ofhard tissue, such as bone. This straight-edge configuration of ashaver-type surgical accessory can also be used to cut soft, fibroustissue. Alternatively, the windows of both the housing element and thecutting head may be provided with toothed or serrated cutting edgeswhich may achieve a more aggressive cut for removal of soft fibroustissue. Other arrangements include providing the window of the housingelement with a straight cutting edge and the window of the cutting headwith a toothed cutting edge. The predominant function of teeth providedon a surgical accessory, and specifically the teeth provided on thecutting head of the inner cutting element of a shaver-type surgicalaccessory, is to pull tissue towards the cutting edge of the outerhousing element window, at which point the tissue is cut by thescissoring action mentioned above.

A bur-type surgical accessory is commonly used to resect bone or otherhard tissues, and includes cutting features which, when the accessory isrotated, serve to cut away such tissue. Such cutting features of thistype of accessory may be helically or non-helically oriented.Non-helically oriented cutting features may be those which extendlinearly or parallel with the axis of the accessory. The cutting elementof a bur-type surgical accessory includes a cutting head with thesecutting features which, in some accessories, are exposed through awindow formed at the distal end of the outer housing element when thecutting element is located therein. In some bur-type surgicalaccessories, the window formed in the outer housing element opensprimarily sidewardly, so that the distal end of the outer housingelement covers a portion or one side of the cutting head of the bur toallow the user to better target bone or hard tissue. Alternatively, theentire cutting head geometry may project distally beyond the terminalend of the outer housing element. A variety of bur geometries areavailable to specifically address the type of cutting the accessory isto carry out.

Additionally, in an endoscopic surgical procedure, irrigating fluid isintroduced into the surgical site, which fluid serves as a transportmedia for removing tissue and debris therefrom. In order to remove theirrigating fluid and the material contained therein, the above-discussedhandpiece and the various accessories which are usable therewithtogether define a suction conduit. In this regard, a suction pump isconnected to the handpiece to provide the suction force needed fordrawing the fluid and material away from the surgical site. In order tocontrol the suction flow through the accessory and the handpiece, thehandpiece is typically provided with a manually operated valve which ismanipulated by the surgeon to control suction of material away from thesurgical site. In a shaver-type surgical accessory, surgical debris issuctioned away through the aligned windows of the outer housing elementand the cutting head of the cutting element, and then evacuated via apassage provided in the surgical accessory. Likewise, some bur-typesurgical accessories incorporate a suction arrangement including asuction opening formed in a distal end of the drive shaft and proximallyof the cutting head, which suction opening communicates with a hollowinterior of the drive shaft. Surgical debris is thus suctioned inwardlyinto the surgical accessory through this suction opening and then into apassage of the drive shaft and away from the accessory. In otherbur-type surgical accessories, such as the one disclosed in U.S. Pat.No. 9,636,131 (owned by the assignee hereof), a suction opening oropenings are provided in the cutting head itself adjacent the cuttingfeatures thereof.

SUMMARY

While the arrangements described above perform well, there is acontinuing desire and need for improved performance in surgicalaccessories in an effort to minimize trauma to the patient and to makethe operative procedure more efficient and effective for both thepatient and the surgeon carrying out the procedure. The surgicalaccessory disclosed herein according to various embodiments is amulti-functional surgical accessory which incorporates two differenttissue-treating areas or tissue-treating configurations which togetherprovide the hard tissue removal, resecting, or cutting action andbenefits of a bur-type cutting accessory, as well as efficientsoft-tissue removal, resection, or cutting and benefits of a shaver-typecutting accessory. Providing this type of geometry on a surgicalaccessory allows the surgeon to efficiently remove both hard and softtissue with a single surgical cutting accessory. As such, the number ofsurgical accessories that are needed during a surgical procedure toachieve the desired result is reduced, which saves time during aprocedure, promotes safety during the procedure and reduces overallequipment costs.

There is provided a surgical accessory for treating a first tissue typehaving a first hardness and for treating a second tissue type having asecond hardness less than the first hardness. The surgical accessoryincludes a cutting element having a proximal end, a distal end spacedtherefrom and a cutting head disposed at the distal end and defining alongitudinal axis. The cutting head may include first and secondtissue-treating areas spaced from one another along an outer peripheralarea thereof which extends about the axis, wherein the firsttissue-treating area and the second tissue-treating area are configureddifferently from one another to provide the cutting head with differenttypes of tissue-treating action. The first tissue-treating area has aregion configured for abrading the first tissue type, which abradingregion extends along a substantial part of the total of the outerperipheral area of the cutting head, and the second tissue-treating areaincludes a region configured for treating the second tissue type.

The cutting head of the surgical accessory may include a wall defining ahollow interior portion within the cutting head with the outerperipheral area being formed on the wall, wherein the region of thesecond tissue-treating area includes a window extending through the wallfor communication with the hollow interior portion.

The wall of the cutting head of the surgical accessory may include apair of edges configured to cut tissue and disposed in opposed andspaced relation with one another at the outer peripheral area, whereinthe edges respectively define substantially opposite sides of thewindow.

The wall of the cutting head of the surgical accessory may be tubular inshape and may extend circumferentially about the axis and terminate atthe respective cutting edges of the second tissue-treating area suchthat the edges thereof define free terminal edges of the wall with thewindow being disposed therebetween.

The wall of the cutting head of the surgical accessory, at an areacorresponding to the first tissue-treating area, may have a greaterthickness than a thickness of the wall at the second tissue-treatingarea.

The first tissue-treating area of the surgical accessory may extendalong a substantial circumferential portion of the outer peripheral areaof the cutting head and may include a solid and non-windowed portion ofthe wall which is not in fluid communication with the hollow interior.

The cutting edges of the second tissue-treating area of the surgicalaccessory may be substantially parallel with one another or may benon-parallel with one another. Further, one or both of the cutting edgesof the second tissue-treating area may include at least one tooth.

The surgical accessory may include an outer housing element having aproximal end and a distal end spaced therefrom, the distal end defininga window including a pair of edges configured to cut tissue and disposedin opposed and spaced relation with one another. Further, the cuttinghead may be disposed within the distal end of the outer housing elementsuch that the cutting edges of the window of the cutting head aredisposed to cooperate with the cutting edges of the window of the outerhousing element to treat tissue located adjacent the windows duringmovement of the cutting head relative to the outer housing element.

The abrading region of the first tissue-treating area of the surgicalaccessory may include a fluted region including a cutting surface and aflute each extending longitudinally along the outer peripheral area ofthe cutting head. The cutting surface and the flute may each extendalong the outer peripheral area either helically about the axis, orlinearly so as to be substantially parallel with the axis.

The abrading region of the first tissue-treating area of the surgicalaccessory may include a plurality of abrasive particles fixed to anexterior surface of the cutting head located on the outer peripheralarea thereof.

The abrading region of the first tissue-treating area of the surgicalaccessory may include a rasp including a plurality of teeth.

The second tissue-treating area of the surgical accessory may benon-fluted.

There is additionally provided a surgical accessory which may include acutting element having a proximal end, a distal end spaced therefrom anda cutting head disposed at the distal end and defining a longitudinalaxis. The cutting head may include a wall defining a hollow interiorportion within the cutting head. The cutting head may include first andsecond tissue-treating areas spaced from one another along an outerperipheral area of the wall of the cutting head, wherein the firsttissue-treating area and the second tissue-treating area may beconfigured differently from one another to provide the cutting head withboth hard and soft tissue-treating action. Further, the secondtissue-treating area may be non-fluted. The first tissue-treating areamay include one of a fluted region or an abrading region, and the secondtissue-treating area may include a window extending through the wall forcommunication with the hollow interior portion. The wall may include apair of edges configured to cut tissue and disposed in opposed andspaced relation from one another at the outer peripheral area, whereinthe edges respectively define substantially opposite sides of the windowand form part of the second tissue-treating area.

There is also provided a surgical tool system including a surgicalaccessory having an outer housing assembly including a hub at a proximalend thereof and an elongate and substantially tubular housing elementhaving a proximal end fixed to the hub and a distal end spacedtherefrom, the distal end defining a housing element window, the housingelement window being defined partially by a pair of edges of the housingelement configured to cut tissue and disposed in spaced relation fromone another along a periphery of the distal end. The surgical accessorymay further include a cutting element assembly for removing a firsttissue type having a first hardness and for removing a second tissuetype having a second hardness less than the first hardness. The cuttingelement assembly may include a hub at a proximal end thereof and a driveshaft disposed within the housing element for movement relative thereto,the drive shaft having a proximal end fixed to the hub of the cuttingelement assembly and a distal end spaced from the proximal end of thedrive shaft. The cutting element assembly may further include a cuttinghead defining an axis, the cutting head having a hollow interior portionand an exterior portion and having first and second tissue-treatingareas spaced peripherally from one another along the exterior portion ofthe cutting head. The first tissue-treating area includes an abradingregion configured for treating the first tissue type, and the secondtissue-treating area includes a cutting head window for treating thesecond tissue type. The cutting head window communicates with the hollowinterior portion of the cutting head, and the cutting head window isdefined partially by a pair of edges of the cutting head which areconfigured to cut tissue and are spaced peripherally from one anothertherealong. The cutting head is disposed within the distal end of thehousing element axially adjacent the housing element window such thatthe cutting edges of the cutting head window are disposed to cooperatewith the cutting edges of the housing element window to treat tissuelocated within the windows during movement of the cutting head relativeto the housing element window.

The cutting edges of said cutting head window of the surgical accessoryof the surgical tool system may be disposed radially closely adjacent tothe cutting edges of the housing element window.

The cutting head of the surgical accessory of the surgical tool systemmay be rotatably movable relative to and within the distal end of thehousing element.

The abrading region of the first tissue-treating area of the surgicalaccessory of the surgical tool system may include a flute disposed incircumferentially adjacent relation with a cutting surface, and theflute and the cutting surface may extend longitudinally along thecutting head either helically about the axis, or linearly insubstantially parallel relation with the axis.

The cutting head of the surgical accessory of the surgical tool systemmay include a wall which defines the hollow interior portion and throughwhich the cutting element window extends, wherein the wall at an areacorresponding to the first tissue-treating area has a greater thicknessthan a thickness of the wall at respective regions of the wall disposedclosely adjacent the edges of the second tissue-treating area.

The abrading region of the cutting head of the surgical accessory of thesurgical tool system may include a plurality of alternating cuttingsurfaces and flutes, with each cutting surface having a terminal outeredge. The wall of the cutting head may define a land immediatelyadjacent each terminal outer edge, with each land having an outerdiameter substantially similar to an inner diameter of an inner surfacedisposed on the distal end of the housing element. Further, each landmay form a bearing surface on the cutting head for cooperation with theinner surface of the housing element during movement of the cutting headrelative thereto.

In the surgical tool system, one of the distal end of the housingelement of the surgical accessory or the cutting head of the surgicalaccessory may include a material having a greater hardness than ahardness of a material of the other of the distal end of the housingelement or the cutting head.

In the surgical tool system, the abrading region of the firsttissue-treating area of the cutting head of the surgical accessory mayinclude a plurality of abrasive particles fixed to the exterior portionof the cutting head.

In the surgical tool system, the abrading region of the firsttissue-treating area of the cutting head of the surgical accessory mayinclude a rasp including a plurality of teeth.

In the surgical tool system, the abrading region of the firsttissue-treating area of the cutting head of the surgical accessory mayextend circumferentially along a substantial portion of the exteriorportion of the cutting head and may be a solid and non-windowed portionthereof which is not in communication with the hollow interior portion.

In the surgical tool system, the second tissue-treating area of thecutting head of the surgical accessory may be non-fluted.

The surgical tool system may include a handpiece and a couplingarrangement for interconnecting the handpiece with the surgicalaccessory.

There is also provided a method of treating tissue at a surgical site,the tissue at the surgical site being of a first tissue type having afirst hardness and a second tissue type having a second hardness lessthan the first hardness. The method includes treating the first tissuetype with an abrading region of a first tissue-treating area provided ona cutting head of a single surgical resection tool, the abrading regionextending along a substantial part of a total outer peripheral area ofthe cutting head, and treating the second tissue type with a secondtissue-treating area provided on the cutting head of the single surgicalresection tool.

The first tissue type includes bone or cartilage or a combinationthereof, and the second tissue type includes ligaments, tendons ormuscle or a combination thereof. In accordance with the method, thetreating of the first tissue type may be performed subsequent to thetreating of the second tissue type.

The method may include operating the single surgical accessory in firstand second opposite rotational directions when treating the secondtissue type.

Additionally, the method may include operating the single surgicalaccessory in a single rotational direction when treating the firsttissue type.

Further, the method may include operating the single surgical accessoryin first and second opposite rotational directions to treat the secondtissue type, and thereafter operating the single surgical accessory inthe first rotational direction to treat the first tissue type.

There is additionally provided a kit for imaging tissue in a surgicalsite, the kit including the surgical accessory or the surgical toolsystem.

Also provided is a fluorescence imaging agent, for use with the surgicalaccessory or the surgical tool system, for imaging tissue in a surgicalsite.

Still further, the surgical accessory, the surgical tool system or themethod of treating tissue may be used in combination with medicalimaging, robotics, or a combination thereof, the medical imagingincluding blood flow imaging, tissue perfusion imaging, tissue anatomyimaging or a combination thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a surgical tool system, including ahandpiece with a multi-functional surgical accessory attached theretoaccording to an embodiment;

FIG. 2 is an enlarged, fragmentary, longitudinal and cross-sectionalview of the handpiece of FIG. 1 with a surgical accessory attachedthereto;

FIG. 3 is an enlarged and fragmentary view of the surgical accessory;

FIG. 4 is an enlarged longitudinal cross-sectional view of the surgicalaccessory of FIG. 3, as seen generally along line IV-IV in FIG. 3;

FIG. 5 is an enlarged and isolated view of an embodiment of the cuttinghead of the surgical accessory;

FIG. 6 is an enlarged and isolated view of the cutting head of thesurgical accessory, rotated approximately 90 degrees from the positionshown in FIG. 5;

FIG. 7 is an enlarged and isolated view of the cutting head of thesurgical accessory rotated approximately 180 degrees from the positionshown in FIG. 5;

FIG. 8 is a cross-sectional view as seen generally along line VIII-VIIIin FIG. 5;

FIG. 9 is an enlarged distal end view as seen along line IX-IX in FIG.6;

FIG. 10 is an enlarged cross-sectional view as seen generally along lineX-X in FIG. 5;

FIG. 11 is an enlarged cross-sectional view similar to that shown inFIG. 10, but illustrating a variation of the cutting head includingrelief angles;

FIG. 12 is an enlarged proximal end view as seen along line XII-XII inFIG. 6;

FIG. 13 is an enlarged and isolated view of another embodiment of thecutting head of the surgical accessory;

FIG. 14 is an enlarged perspective view of the cutting head of thesurgical accessory shown in FIG. 13;

FIG. 15 is an enlarged and fragmentary perspective view of a furtherembodiment of the cutting head of the surgical accessory;

FIG. 16 is an enlarged and fragmentary perspective view of the cuttinghead of the surgical accessory rotated approximately 90 degrees from theposition shown in FIG. 15;

FIG. 17 is an enlarged and fragmentary perspective view of a furtherembodiment of the cutting head of the surgical accessory;

FIG. 18 is an enlarged and fragmentary perspective view of the cuttinghead of the surgical accessory rotated approximately 90 degrees from theposition shown in FIG. 17;

FIG. 19 is an enlarged and fragmentary perspective view of theembodiment of the cutting head of the surgical accessory shown in FIGS.15 and 16, with the cutting element of the accessory located within theouter housing element;

FIG. 20 is an enlarged and fragmentary perspective view similar to FIG.19, but with the cutting element rotated approximately 180 degreesrelative to the outer housing element from the position shown in FIG.19;

FIG. 21 is an enlarged and isolated view of a further embodiment of thecutting head of the surgical accessory;

FIG. 22 is an enlarged and isolated view of the cutting head of thesurgical accessory rotated approximately 180 degrees from the positionshown in FIG. 21;

FIG. 23 is an enlarged and isolated perspective view of the cutting headof the surgical accessory shown in FIGS. 21 and 22;

FIG. 24 is an enlarged cross-sectional view as seen generally along lineXXIV-XXIV in FIG. 21;

FIG. 25 is an enlarged and isolated view of a further embodiment of thecutting head of the surgical accessory;

FIG. 26 is an enlarged and isolated view of the cutting head of thesurgical accessory rotated approximately 180 degrees from the positionshown in FIG. 25;

FIG. 27 is an enlarged and isolated perspective view of the cutting headof the surgical accessory shown in FIGS. 25 and 26;

FIG. 28 is an enlarged proximal end view as seen generally along lineXXVIII-XXVIII in FIG. 26;

FIG. 29 is an enlarged cross-sectional view as seen generally along lineXXIX-XXIX in FIG. 25;

FIG. 30 is an enlarged perspective view of a further embodiment of thecutting head of the surgical accessory;

FIG. 31 is an enlarged plan view of the cutting head of the surgicalaccessory of FIG. 30;

FIG. 32 is an enlarged view of the cutting head of the surgicalaccessory rotated approximately 180 degrees from the position shown inFIG. 31;

FIG. 33 is an enlarged view of the cutting head of the surgicalaccessory rotated approximately 90 degrees from the position shown inFIG. 31;

FIG. 34 is an enlarged distal end view as seen along line XXXIV-XXXIV inFIG. 33;

FIG. 35 is an enlarged proximal end view as seen along line XXXV-XXXV inFIG. 33;

FIG. 36 is an enlarged perspective view of a further embodiment of thecutting head of the surgical accessory;

FIG. 37 is an enlarged plan view of the cutting head of the surgicalaccessory of FIG. 36;

FIG. 38 is a cross-sectional view as seen generally along lineXXXVIII-XXXVIII in FIG. 37;

FIG. 39 is an enlarged view of the cutting head of the surgicalaccessory rotated approximately 180 degrees from the position shown inFIG. 37;

FIG. 40 is an enlarged distal end view as seen along line XL-XL in FIG.39;

FIG. 41 is an enlarged proximal end view as seen along line XLI-XLI inFIG. 39;

FIG. 42 is a cross-sectional view as seen generally along line XLII-XLIIin FIG. 39;

FIG. 43 is an enlarged perspective view of a further embodiment of thesurgical accessory, including a variation of the distal end of the outerhousing element shown in isolation;

FIG. 44 is an enlarged side view of the surgical accessory of FIG. 43;

FIG. 45 is an enlarged view of the surgical accessory, rotatedapproximately 90 degrees from the position shown in FIG. 44;

FIG. 46 is an enlarged and fragmentary perspective view of the surgicalaccessory of FIGS. 43-45, including a further variation of a cuttinghead located within the outer housing element;

FIG. 47 is an enlarged distal end view as seen along line XLVII-XLVII inFIG. 46;

FIG. 48 is an enlarged and isolated perspective view of a furtherembodiment of the surgical accessory, including a further variation ofthe distal end of the outer housing element shown in isolation;

FIG. 49 is an enlarged side view of the surgical accessory of FIG. 48;

FIG. 50 is an enlarged and fragmentary perspective view of the surgicalaccessory of FIGS. 48 and 49, including the cutting head of theembodiment of FIGS. 46 and 47 located within the outer housing element;

FIG. 51 is an enlarged distal end view as seen along line LI-LI in FIG.50;

FIG. 52 is an enlarged and fragmentary cross-sectional view of avariation of the drive shaft shown in FIGS. 2 and 4;

FIG. 53 is an enlarged perspective view of a further embodiment of thecutting head of the surgical accessory;

FIG. 54 is an enlarged plan view of the cutting head of the surgicalaccessory of FIG. 53;

FIG. 55 is an enlarged view of the cutting head of the surgicalaccessory rotated approximately 180 degrees from the position shown inFIG. 54;

FIG. 56 is an enlarged view of the cutting head of the surgicalaccessory rotated approximately 90 degrees from the position shown inFIG. 54;

FIG. 57 is an enlarged distal end view as seen along line LVII-LVII inFIG. 56;

FIG. 58 is an enlarged proximal end view as seen along line LVIII-LVIIIin FIG. 56;

FIG. 59 is an enlarged cross-sectional view as seen generally along lineLIX-LIX in FIG. 54;

FIG. 60 is an enlarged and fragmentary perspective view of the cuttinghead of FIGS. 53-59, assembled within an outer housing element;

FIG. 61 is an enlarged and fragmentary plan view of the surgicalaccessory shown in FIG. 60;

FIG. 62 is an enlarged and fragmentary view of the surgical accessoryrotated approximately 90 degrees from the position shown in FIG. 61;

FIG. 63 is an enlarged cross-sectional view as seen generally along lineLXIII-LXIII in FIG. 61; and

FIG. 64 is an enlarged cross-sectional view as seen generally along lineLXIV-LXIV in FIG. 61.

Certain terminology will be used in the following description forconvenience in reference only, and will not be limiting. For example,the words “upwardly”, “downwardly”, “rightwardly” and “leftwardly” willrefer to directions in the drawings to which reference is made. Thewords “inwardly” and “outwardly” will refer to directions toward andaway from, respectively, the geometric center of the system anddesignated parts thereof. The words “forwardly” and “distally” willrefer to the direction toward the end of the system which is closest tothe patient, and the words “rearwardly” and “proximally” will refer tothe direction toward the end of the system which is furthest from thepatient. Said terminology will include the words specifically mentioned,derivatives thereof, and words of similar import.

DETAILED DESCRIPTION

Reference will now be made in detail to implementations and embodimentsof various aspects and variations of the invention, examples of whichare illustrated in the accompanying drawings. Although variations of thesystems, methods, uses and kits are described, other variations of thesystems, methods, uses and kits may include aspects of the systems,methods, uses and kits described herein combined in any suitable mannerhaving combinations of all or some of the aspects described.

Referring to FIGS. 1 and 2, an exemplary surgical tool system 10 formanipulating tissue at a surgical site 10A is illustrated. The system 10includes a handpiece 11, which at its distal end mounts thereon (orcouples thereto) a multi-functional surgical accessory 12 for cutting orresecting tissue. The tool system 10 may be utilized with a medicalimaging system 10B. The medical imaging system 10B may include anendoscopic camera 10C, a camera control unit 10D for controlling thecamera 10C and a light source 10E which cooperates with the camera 10Cto provide light to the surgical site 10A. Further, an image or videoobtained by the endoscopic camera 10C may be displayed on a monitor (notshown) for use by the surgeon. The tool system 10 may also be utilizedwith a robotic system 10F, which system 10F may in some embodimentsinclude a robotic arm which can be used to hold and/or manipulate theendoscopic camera 10C.

The handpiece 11 may be a commercially available surgical handpiece. Forexample, the handpiece 11 may be a handpiece manufactured by theassignee hereof, under Model Nos. 375-704-500, 375-701-500 and375-708-500, and is accordingly only briefly described herein. Forexample, the handpiece 11 includes an elongate outer housing 13 definingan elongate bore 14 therein. A motor 15 (shown diagrammatically only inFIG. 1) is disposed within the housing bore 14. The motor 15 includes anoutput or drive shaft 16, which drive shaft 16 mounts a drive pin 17 atthe distal end thereof. A power cable 18 is coupled to the proximal endof the handpiece 11 for supplying power to the motor 15.

In the example in FIG. 1, the handpiece housing 13 defines therein anelongate suction bore (not shown) extending generally parallel to andsidewardly of the housing bore 14. This suction bore communicates with adiagonally extending suction passage 20 defined in the housing 13, whichpassage 20 provides communication between the distal end of the housingbore 14 and the suction bore. Suction is drawn through the handpiece 11by a suction pump (not shown), which is connected to the handpiece 11via a suction tube 21. Suction flow through the handpiece 11 isregulated by an adjustable valve 22 having a valve stem (not shown)which is movably mounted in a valve bore 23 defined in the housing 13.The valve 22 is adjusted by the user via a movable handle or arm 24connected to the valve stem.

The surgical accessory 12 is removably attachable to the distal end ofthe handpiece 11 by, for example, a coupler such as a coupling assembly25 in the example in FIG. 1 which is provided on the handpiece 11. Thecoupling assembly 25 in the example in FIG. 1 may include, for example,as is illustrated in FIG. 2, a generally ring-shaped collet 26 securedto the distal end of the handpiece housing 13. A locking ring 27 ismovably disposed in the collet 26 and is biased to hold the surgicalaccessory 12 within the housing bore 14 of the handpiece 11. A releasebutton 28 is provided on the locking ring 27, and is used to release thelocking ring 27 and allow removal of the surgical accessory 12 from thehandpiece 11. Further, a coil 30 is provided in the collet 26, which isused to facilitate inductive signal transfer to/from a radio-frequencyidentification device (RFID) disposed in the surgical accessory 12 asdiscussed below.

Referring to FIGS. 2-4, the surgical accessory 12 will now be describedaccording to the various embodiments. The surgical accessory 12 isconfigured as a multi-functional device in that same incorporatesmultiple tissue-treating areas in a single device, one of which areascan be used to carry out hard tissue removal, resection or cutting suchas the removal of cortical bone, cancellous bone or cartilage, and theother of which areas can be used to carry out soft-tissue removal,resection or cutting such as the removal, resection or cutting of softconnective tissue including, for example, ligaments, tendons or muscle.Examples of various implementations which can be used to provide suchfunctionality for a surgical accessory are described below.

In the embodiment illustrated in FIGS. 2-4, the surgical accessory 12defines a central longitudinal axis 31 (FIG. 3), and includes an outercannula or tubular housing element 32 and a tubular cutting element 33disposed within the housing element 32. The housing element 32 includesa hub 34 which defines the proximal end thereof. The hub 34 is definedby a generally tubular base body 35, which defines therein a pair ofgenerally rectangular and diametrically-opposed openings 36 adjacent theproximal end thereof. The base body 35 also has formed thereon a pair ofoutwardly-projecting, diametrically opposed and generally ramp-shapedears 37 disposed distally of the openings 36. The ears 37 cooperate withthe coupling assembly 25 of the handpiece 11 to secure the accessory 12therein. The hub 34 has a distal end defined by a head 39 or nose of areduced diameter as compared to the base body 35. Further, the hub 34defines therein a bore 41 which extends completely through the hub 34,and with which the openings 36 of the base body 35 communicate.

In the embodiment illustrated in FIGS. 2-4, an annular seal 45 isdisposed within the proximal end of the bore 41 of the hub 34. The seal45 is constructed of a resilient elastomeric material, and is defined bya main section 46 and axially-spaced proximal and distal sections 47 and48 disposed at respective opposite ends of the main section 46. Theproximal section 47 defines thereon a pair of annular ribs 55 and 56,which are disposed in sealing engagement with an inner annular surfaceof the collet 26 of the handpiece 11 when the accessory 12 is coupledthereto, as shown in FIG. 2. The distal section 48 defines thereon apair of outwardly projecting and diametrically-opposed lock tabs 57which engage within the respective openings 36 of the hub 34 to securethe seal 45 to the hub 34 and fix the axial position of the seal 45relative thereto. The distal section 48 additionally defines thereon apair of inwardly projecting and diametrically-opposed stop tabs 58,which are generally radially aligned with the respective lock tabs 57.As shown in FIGS. 2 and 4, an RFID device 59 encapsulated within a ringstructure is located within the hub bore 41 distally from, and inaxially-adjacent relationship with, the distal section 48 of the seal45.

The housing element 32 (FIGS. 2-4) additionally includes an elongatehousing tube 64 which projects distally from the hub 34. Morespecifically, the housing tube 64 has a proximal end which is fixedlymounted within the distal portion of the bore 41 of the hub 34. Thehousing tube 64 defines an elongate bore or conduit 65 therein, in whichthe cutting element 33 is disposed as discussed below. Referring toFIGS. 3 and 4, the housing tube 64 has a distal end 66 which in theillustrated embodiment is cut so as to define a window 67 having anannular edge 68, which window 67 in the illustrated embodiment opensboth sidewardly and distally of the tube 64. The annular edge 68includes a pair of cutting edges 68A and 68B oriented in substantiallyopposed relation with one another and which are spaced circumferentially(or sidewardly-spaced) from one another along the distal end 66 of thehousing tube 64. The annular edge 68, with its cutting edges 68A and68B, is formed as a result of a cutting operation performed on thedistal end 66 of the housing tube 64, and thus these edges effectivelydefine free and circumferentially extending terminal edges of thehousing tube 64 so as to form the window 67.

Turning now to the cutting or resecting element 33, same includes a hub80 which defines the proximal end thereof. The hub 80 incorporates amotor-engaging drive element 81 defining a proximally opening bore 82,and a slot 84 which extends transversely to the longitudinal axis of thecutting element 33. The hub 80 additionally includes a neck 85 whichprojects distally from the drive element 81. The neck 85 terminates at ahead 86 which has an enlarged outer diameter. In this regard, the outerdiameter of the head 86 is slightly larger than the inward projection ofthe respective stop tabs 58 of the seal 45. A bore 87 extends throughthe neck 85 and the head 86, in which an elongate and tubular driveshaft 88 is fixed. In this embodiment, the drive shaft 88 definestherein a suction passage 89 which is in communication with a suctionport 90 defined in the neck 85, which suction port 90 is in turn incommunication with the suction passage 20 of the handpiece 11.

The drive shaft 88 has a distal end 91 which mounts a cutting head 104thereon. In the illustrated embodiment, the drive shaft 88 and thecutting head 104 are constructed as separate components which are fixedto one another. In this regard, the drive shaft 88 may be constructed ofa rigid plastic and then induction welded to the cutting head 104, whichmay be constructed of rigid metal, such as stainless steel.Alternatively, the drive shaft 88 and the cutting head 104 may beconstructed as an integral or one-piece member formed from rigid metal,such as stainless steel. The cutting head 104 is substantiallycylindrical and tubular in the illustrated embodiment, and defines ahollow interior 105 which extends along substantially the entirelongitudinal extent of the cutting head 104 and in this embodimentcommunicates with the suction passage 89 of the drive shaft 88. It willbe appreciated that the drive shaft 88 need not be hollow as shown, andinstead may be provided as a solid member which may be rigid orflexible, as discussed further below.

As shown in detail in the embodiment in FIG. 8, the cutting or resectinghead 104 includes a substantially tubular or substantially cylindricalwall 108 with a tubular proximal end portion 106 of a generally constantdiameter and a distal end portion 107 connected to and extendingdistally from the proximal end portion 106. The wall 108 has an exteriorsurface 109 extending both circumferentially and axially, and aninterior surface 111 facing opposite the exterior surface 109 anddefining the interior 105 of the cutting head 104. The cutting head 104,and particularly the distal end portion 107 thereof, is provided withdifferent and distinct types of tissue-treating areas, which areas maybe utilized to carry out tissue removal, tissue-cutting ortissue-resection, which areas are spaced from one another along thecircumference of the cutting head 104. In this embodiment, these areasare located on opposite sides of the cutting head 104. As shown in theembodiment in FIG. 7, a first of these tissue-treating areas 110 is acircumferentially-extending abrading surface or region, which in thisembodiment has a bur configuration incorporating a fluted region whichin this embodiment includes a plurality of cutting surfaces 115 andflutes 117 oriented in an alternating manner with one another along partof the circumference of the cutting head 104. The cutting surfaces 115and flutes 117 in this embodiment extend in a helical manner about theaxis 114 and in a generally parallel manner with one another along amajority of the longitudinal extent of the distal end portion 107. Eachcutting surface 115 terminates at a cutting edge 113 which defines theradially outermost extent thereof. The terminal cutting edges 113 extendgradually towards one another in the proximal to distal direction andterminate adjacent a tip 116 of the distal end portion 107, as bestshown in FIGS. 6 and 9. In the illustrated embodiment, the terminaledges 113 stop proximally of the tip 116, which effectively creates abearing surface 116A at the tip 116. Such a bearing surface provides asupport surface which cooperates with an adjacent interior surface ofthe distal end 66 of the housing tube 64 to support the cutting element33 during movement relative to the housing element 32 as discussedbelow. It will be appreciated that the cutting surfaces 115 and theflutes 117 may alternatively be non-helical or substantially straight orlinear so as to extend generally parallel with the axis 114 as shown indotted lines in FIG. 6, or so as to be oriented at an angle relative tothe axis 114.

In this embodiment, the first tissue-treating area 110 extends along asubstantial circumferential portion of the exterior surface 109 of thecutting head 104, and the portion of the wall 104 on which the firsttissue-treating area 110 is formed is solid and does not include anywindows or openings which communicate with the interior 105 of thecutting head 104.

In the illustrated embodiment and with reference to FIG. 10, on the sideof the cutting head 104 on which the first tissue-treating area 110 isprovided, the portions of the wall 108 located between neighboring pairsof cutting surfaces 115 (which portions define the respective flutes117) are provided with lands 118. More specifically, the flute 117 ofthe cutting head 104 is formed so as to leave remaining a land 118between adjacent pairs of cutting surfaces 115. As such, in theillustrated embodiment, the land 118 has a contour which correspondswith the curvature of the exterior surface 109 of the cutting head 104.As shown in FIGS. 7, 9 and 10, each land 118, in addition to extending ashort distance circumferentially along the cutting head 104, alsoextends substantially longitudinally along the cutting head 104, andfollows the contour of the helix of the cutting surfaces 115 and flutes117. In one embodiment, the lands 118 have a circumferential dimension,based on a cutting head 104 with a 5.5 mm diameter, of approximately0.020 inch. In another embodiment, for a cutting head 104 with a 4.0 mmdiameter, the circumferential dimension of the lands 118 isapproximately 0.010 inch. In other embodiments, the circumferentialdimension for these sizes of cutting heads 104 may be in the range of0.005-0.040 inch. The lands 118 serve to minimize wear on the interiorsurface of the housing tube 64 of the outer housing element 32 duringoperation of the surgical accessory 12, as discussed in further detailbelow.

The cutting head 104, on a region thereof circumferentially-spaced fromthe first tissue-treating area 110, is provided with a secondtissue-treating area 119 having a windowed configuration as shown in theembodiment in FIGS. 5 and 6. In this embodiment, the area 110 is locatedsubstantially diametrically opposite the area 119. Further, the area 119is non-fluted. In this regard, the wall 108 at the distal end portion107 of the cutting head 104 is cut to define a window 122, which window122 is formed as an elongated opening in the cutting head 104. In theillustrated embodiment, the window 122 opens primarily sidewardly ortransversely relative to the axis 114 and communicates with the interior105 of the cutting head 104. One side of the window 122 defines a firstcutting edge 123, which cutting edge 123 is smooth and substantiallylinear. Further, and with reference to FIG. 5, the edge 123 in theillustrated embodiment angles inwardly as same extends longitudinallyalong the cutting head 104 in a distal to proximal direction. Theopposite side of the window 122, disposed in substantially facing andopposed relation with the first cutting edge 123, defines a secondcutting edge 124 which in this embodiment is provided with at least one,and here a plurality, of teeth 125. In the illustrated embodiment, theteeth 125 are of gradually increasing depth (wherein the depth isconsidered to encompass the distance from the root or base of the tooth125 to the tip thereof) as the teeth 125 progress in the distal toproximal direction. Additionally, the terminal outer ends of the teeth125 may be aligned with one another as shown so that same substantiallyfollow the helical angle of the cutting surfaces 115 and flutes 117. Itwill be appreciated that the configuration of the teeth 125 as shown isan example of only one type of tooth configuration, and other toothconfigurations are usable. In this regard, other applicable toothconfigurations may include a lesser or greater number of teeth than thatshown. Further, the tooth depths may be constant or substantially equalto one another. Additionally, the placement of the teeth along thecutting edge 124 may differ from that shown, in that the teeth may bespaced a greater or lesser distance from one another. Further, thecutting edge 124 may instead be non-toothed such that the edge 124 isangled in the manner shown in FIG. 5, but instead has a smooth edge inplace of the teeth 125 as shown in dotted lines in the embodiment inFIG. 6. Additionally, the cutting edge 123 may include one or more teeth125A as shown in dotted lines in FIG. 5.

As best shown in FIGS. 5 and 9, the window 122 additionally includes adistal cutting edge 126, which in the illustrated embodiment is arcuateand extends between and interconnects the opposed first and secondcutting edges 123 and 124.

It will be appreciated that the cutting window 122 may be provided withvarious geometries based on the type of cutting action the cutting head104 is intended to carry out. For example, the teeth 125, 125A of thecutting edge 124 may be provided with an internal shear angle in orderto achieve the desired cutting action. In this regard, “shear angle” inthis context is intended to refer to the opening angle of the window 122which is determined during the cutting process which forms the window.For example, the teeth may be provided with a negative internal shearangle which less than zero degrees, a positive internal shear anglewhich is greater than zero degrees, or a zero degree shear angle.Further, the teeth may be provided with no shear angle, meaning that theinternal cutting face of the tooth is oriented in a plane whichintersects the central axis 114 of the cutting head 104. The oppositecutting edge 123 and/or the proximal cutting edge 126 may also beprovided with the various geometries discussed above, if desirable ornecessary.

Referring to FIGS. 8 and 10, the cylindrical wall 108 of the cuttinghead 104 has a thickness dimension 108A, as defined between the exteriorsurface 109 and the interior surface 111 thereof, which is greater inthe area of the first tissue-treating area 110 as compared to the wallthickness of the wall 108 on the side or in the region of the secondtissue treating area 119. More specifically, the wall 108, as sameextends circumferentially about the cutting head 104, gradually lessensin its thickness dimension as same approaches the cutting edges 123 and124 of the second tissue-treating area 119. Additionally, the wall 108has the thickness dimension 108A from adjacent the proximal originationpoint of the edges 113 up to the distal cutting edge 126.

This increased wall thickness 108A of the wall 108 in the area of thefirst tissue-treating area 110 provides the cutting head 104 withincreased rigidity and structural integrity in this area to permit theformation, for example by machining, of the cutting surfaces 115, theflutes 117 and the lands 118 of the area 110. As shown in FIGS. 8, 10and 12, the interior surface 111, in the area of the proximal end 106 ofthe cutting head 104, defines a first bore 111A which is centered on thecentral axis 114 of the cutting head 104 to allow attachment of thecutting head 104 to the drive shaft 88 of the surgical accessory 12. Inthe area of the tissue-treating areas 110 and 119, the interior surface111 defines a second bore 111B disposed axially adjacent and distally ofthe first bore 111A, which second bore 111B has a central axis 114Aradially offset from the central axis 114 to provide the increased wallthickness of the wall 108 adjacent the first tissue-treating area 110 asdiscussed above. This offset bore configuration, and specifically theformation of the second bore 111B with its axis 114A offset from thecentral axis 114 of the cutting head 104, allows the formation of alarger space within the cutting head 104 for evacuating surgical debrisfrom the surgical site after same enters the window 122, and at the sametime provides a greater wall thickness in the area of the bur-type firsttissue-treating area 110. The second bore 111B as discussed above has acircular cross-section. Alternatively, and as shown in dotted lines inFIG. 10, the second bore, indicated with reference number 111C, may havea non-circular configuration, such as an elongated or oval configurationwith its axis aligned with axis 114 or offset therefrom. In thisembodiment, the radial distance between the dotted line which representsthe bore 111C and the base of each of the flutes 117 of the firsttissue-treating area 110 is substantially the same, which providessufficient thickness and strength to the wall 108 in the area of thefirst tissue-treating area 110. However, the area of the non-circularsecond bore 111C is greater than the area of the circular second bore111B, which maximizes the suction area for removing debris. The secondbore may also have other configurations, such as a D-shapedconfiguration, with the straight part of the D-shape being locatedcircumferentially adjacent the first tissue-treating area 110 in orderto provide sufficient material thickness in this area as discussedabove. Still further, the second bore may have a configuration 111D suchas that shown in dotted lines in FIG. 11, wherein parts of the secondbore adjacent the first tissue-treating area copy or substantiallyfollow the geometry thereof, in order to maximize both the thickness ofthe wall and the cross-sectional area of the suction path. Alternativelyto providing two bores within the cutting head 104 as discussed above,it is also possible to provide a single bore of a constant diameterthrough the cutting head 104, which single bore is of a diameter smallenough to allow both a cutting window and flutes to be formed on thecutting head 104.

The above-described configuration of the wall 108 of the cutting head104 of the surgical accessory 12 allows the cutting head 104 to includeboth a hard-tissue abrading region, such as the first tissue-treatingarea 110, and a soft-tissue removing region, such as the secondtissue-treating area 119, on a single cutting head 104. Thecircumferential surface region of the cutting head 104 which is occupiedby the first tissue-treating area 110 should be chosen so that a maximumnumber of flutes 117 can be provided to achieve efficient hard-tissueremoval. In this regard, in one embodiment, the first tissue-treatingarea 110 occupies approximately 180 degrees or half of the circumferenceof the cutting head 104. In other embodiments, the first tissue-treatingarea 110 may occupy between 45-270 degrees of the circumference of thecutting head 104.

FIG. 11 is a transverse cross-sectional view of a variation of thecutting head 104 discussed above. Components of this variation which aresimilar or identical to components of the first-described embodimentwill include the same reference numbers plus “100”, and a detaileddescription of all components will accordingly not be provided. Inaccordance with this variation, the cutting head 204, in the area of thefirst tissue-treating area 210, is provided with relief angles C. Morespecifically, a relief angle C is cut into the wall 208 of the cuttinghead 204 between neighboring pairs of cutting surfaces 215, which reliefangle C results in the formation of a flat 218. Each flat 218 originatesat a respective terminal edge 213 of a cutting surface 215 and extendsin a circumferential direction away therefrom and towards the adjacentnext cutting surface 215. Providing the cutting head 204 with reliefangles C results in sharper terminal edges 213, which allows moreaggressive tissue removal from a surgical site.

The cutting element 33 is assembled to the outer tubular housing element32 by inserting the distal end 91 of drive shaft 88 of the cuttingelement 33 into the bore 41 at the proximal end of hub 34. During thisinsertion, the enlarged head 86 of the hub 80 expands the seal 45 andthe head 86 pushes past the stop tabs 58, at which point the seal 45essentially resumes its original shape. The stop tabs 58, while allowingsome axial displacement of the cutting element 33 relative to thehousing element 32, prevent the cutting element 33 from detaching orfalling out of the housing element 32 due to gravitational forces.

The assembled surgical accessory 12 is secured to the handpiece 11 byinserting the hubs 34 and 80 into the open distal end of the collet 26.The ears 37 of the hub 34 seat within the collet 26, and the lockingring 27 serves to hold the surgical accessory 12 within the handpiece11. The above securement of the surgical accessory 12 to the handpiece11 causes the drive element 81 to engage the motor output shaft 16. Morespecifically, the drive pin 17 of the output shaft 16 seats within theslot 84 of the drive element 81, such that the rotational movement ofthe output shaft 16 is transferred to the cutting element 33. It will beappreciated that the handpiece 11 and the coupling arrangement thereofwhich cooperates with the surgical accessory 12 as described above isonly an example of one type of handpiece which may be utilized with thesurgical accessory 12. In this regard, the surgical accessory may beconfigured to cooperate with other types of handpieces which handpiecesmay incorporate alternative arrangements for purposes of coupling to thesurgical accessory. For example, a chuck-type coupling arrangement canbe utilized to fixedly attach the surgical accessory 12 to thehandpiece. Other types of coupling arrangements may be utilized,provided that same maintain the outer housing element 32 non-rotatablerelative to the handpiece and provide an appropriate driving engagementof the cutting element 33.

In operation, the distal end of the surgical tool system 10 is insertedinto the surgical site 10A. The cutting element 33 is controlled by acontrol unit (not shown) connected to the handpiece cable 18, whichcontrol unit supplies electrical power to the motor 15 of the handpiece11 in order to actuate the cutting element 33 and control the rotationalspeed thereof. If cutting of tissue is desired, then the motor 15 isactivated so as to cause the cutting element 33 to rotate within andrelative to the outer housing element 32. In this regard, it will beappreciated that the control unit may include appropriate controls(e.g., control buttons) so as to allow the surgeon or operator to selectthe desired operations for the surgical accessory 12. These controlfunctions of the cutting element 33 may alternatively be performeddirectly from the handpiece 11 which would then include the appropriatecontrol buttons thereon. Alternatively, the control unit may beassociated with a switch, either through a suitable cable or wirelessly,to allow the surgeon to operate the controls remotely. Such a switch maybe a footswitch or a hand switch.

As shown in FIGS. 3 and 4, with the cutting element 33 disposed withinthe housing element 32 and the accessory 12 secured to the handpiece 11as described above, the cutting head 104 is positioned axially adjacentthe window 67 of the housing element 32 so that at least a portion ofthe cutting head 104 is exposed through the window 67. In this assembledconfiguration of the cutting element 33 and housing element 32, theedges 123 and 124 are disposed radially closely adjacent to the interiorsurface of the housing element 32, so that the edges 123 and 124 are ina position to cooperate with the edges 68A and 68B of the housingelement 32. During rotation of the cutting element 33 within andrelative to the housing element 32, the bearing surface 116A at the tip116 of the cutting head 104 and the lands 118 provided on the cuttinghead 104 in the embodiment of FIG. 10 serve as support surfaces whichcooperate with the respective adjacent interior surfaces of the distalend 66 of the housing tube 64. The bearing surface 116A and the lands118 assist in minimizing or at least reducing vibration of the cuttingelement 33 relative to the housing element 32, and also assist inminimizing or at least reducing particle generation during movement ofthe cutting element 33 relative to the housing element 32. In thisregard, the lands 118 are particularly effective in reducing particlegeneration when a lateral or transverse force is applied to the surgicalaccessory 12 during a hard-tissue removal operation as discussed furtherbelow. These features which achieve reduction of vibration and particlegeneration serve to minimize wear of the components while ensuring goodcutting or resecting performance, as discussed further below. In thevariation of FIG. 11, no such bearing areas are provided due to theprovision of the relief angles C which form the flats 218, as thisvariation is intended to provide a more aggressive cutting action. Inthis regard, in the embodiment of FIG. 10 which includes the lands 118,the relief angle is essentially zero degrees, meaning that the portionof the land 118 immediately circumferentially adjacent the terminal edge113 of the adjacent cutting surface 115 corresponds to a tangent of theouter curved surface of the cutting head 104 immediately adjacent aterminal edge 113 thereof. In the embodiment of FIG. 11, the cuttinghead 104 is provided with relief angles C resulting in the respectiveflats 218. The relief angle C may have a value in the range of zerodegrees, which corresponds to the embodiment of FIG. 10 and results inthe formation of lands 118, upwards to about forty degrees, whichresults in the formation of straight areas or flats 218 as shown in FIG.11. One preferred range of the relief angle C is zero degrees to twentydegrees.

As shown in FIG. 3, with the cutting element 33 disposed within thehousing element 32 and the surgical accessory 12 secured to thehandpiece 11, the surgical accessory 12 can be operated to remove hardand soft tissue in various modes of operation, based on surgeonpreference and/or the type of surgery which is being carried out.According to one method of operation, the surgical accessory 12 may beoperated first in an oscillating mode and thereafter may be operated ina continuous mode. For example, when the cutting element 33 is operatedin the oscillating mode, the cutting element 33 is rotated a specifiednumber of 360 degree cycles in a forward direction R1, before reversingand rotating a specified number of 360 degree cycles in an opposite orreverse direction R2. This oscillating mode of the surgical accessory 12is useful in preparing the targeted area for a hard-tissue removal,resection or cutting operation by first removing, resecting or cuttingsoft tissue from the targeted area. More specifically, when the cuttingelement 33 is rotated by the handpiece motor 15 in the forward directionR1, the edge 123 of the window 122 of the second tissue-treating area119 of the cutting element 33 moves towards or approaches the edge 68Aof the housing window 67, and soft tissue is cut by the scissoringaction between the opposed edges 123 and 68A as the window closes 67 dueto continued rotation of the cutting element 33 in direction R1. Afterthe cutting element 33 has rotated through the specified number ofcycles in the forward direction R1, the cutting element 33 changesdirection and rotates in the reverse direction R2. When the cuttingelement 33 is rotated in the reverse direction R2, the edge 124 of thewindow 122 of the second tissue-treating area 119 of the cutting element33 moves towards or approaches the edge 68B of the housing window 67 andthe tooth or teeth 125 of the edge 124 grab and pull soft or fibroustissue into the housing tube window 67 and towards the edge 68B thereof.This tissue is cut by the scissoring action between the tooth or teeth125 and the opposed edge 68B of the housing tube window 67 as samecloses due to continued rotation of the cutting element 33 in directionR2.

After completion of the oscillating mode of the surgical accessory 12 asdescribed above, same may then be operated in the continuous mode. Inthis mode, the cutting element is rotated through continuous 360 degreecycles in the forward direction R1 at a relatively high speed in orderto remove or resect hard tissue. More specifically, as the cuttingelement 33 rotates in the direction R1, the first tissue-treating area110 approaches and eventually aligns with the housing window 67, andwhen the area 110 is exposed through the window 67, then hard tissue isresected by the area 110. After this continuous mode of operation wherethe cutting element 33 is rotated in direction R1 is carried out, it maybe preferable to rotate the cutting element 33 in direction R2 toprovide a finishing or polishing operation on the targeted tissue.

In some types of surgery, it may be desirable to initially operate thesurgical accessory 12 in a continuous and relatively high-speed forwardmode (direction R1) so as to clear the targeted site of soft tissue inorder to expose the hard tissue or bone for an abrading operation. Inthis mode, the cutting element 33 is rotated continuously in directionR1 at a high speed, which serves to tear off soft fibrous tissue andclear the site for an abrading operation. In some cases, this mode maybe more effective for removing soft tissue as compared to thepreparatory oscillating mode described above.

As discussed above, the edge 123 of the window 122 provided on thecutting head 104 may, in some embodiments, be provided with a tooth orteeth 125A. Providing teeth on both sides of the window 122 of thecutting head 104 in this manner may serve to improve soft-tissueresecting performance, for example when the surgical accessory 12 isoperated in the oscillating mode described above. In this regard, thetooth 125A in this embodiment is of a larger size than the teeth 125provided along the opposite cutting edge 124 so as to be capable ofresecting hard or bony tissue or so to at least be capable ofwithstanding the impact of hard tissue thereon, since the tooth 125A isoriented in the hard-tissue resecting direction as determined by theconfiguration (for example, based on the rake direction) of the firsttissue-treating area 110.

If desirable or necessary, suction can be provided at the surgical siteby manipulating the valve 22 on the handpiece 11 to draw surgical debrisfrom the surgical site through the rotationally aligned windows 67 and122 of the outer housing element 32 and the cutting element 33, into thedrive shaft suction passage 89, into the handpiece suction passage 20and proximally through the handpiece 11 towards the suction pump.

The surgical accessory with the distal end which incorporates twodifferently configured types of tissue-treating areas as discussed indetail above achieves excellent resecting or cutting performance whileminimizing wear. This may be achieved, at least in part, by providingthe housing tube 64 of the housing element 32 with a greater hardness ascompared to the cutting head 104, or by providing the cutting head 104with a greater hardness as compared to the housing tube 64. For example,both the housing tube 64 and the cutting head 104 may both beconstructed of surgical-grade or high-grade stainless steel and thenboth surface treated to increase the hardness thereof, with the housingtube 64 undergoing a surface-treatment which ultimately provides thehousing tube 64 with a greater hardness than the cutting head 104. Inone embodiment, the housing tube 64 may be constructed of Type 304stainless steel which at a minimum is surface treated to approximately860 HV, and preferably to approximately 900+ HV. The cutting head 104may be constructed of Type 440A stainless steel which at a minimum issurface treated to approximately 50 HRc, and preferably betweenapproximately 50-55 HRc.

The surface-treating or hardening assists in preventing or at leastminimizing flaking and/or particle generation due to the relativemovement between the cutting element 33 and the inner surface of thehousing tube 64. Additionally, the lands 118 provided on the cuttinghead 104 also serve to minimize particle generation which can occurduring this relative movement. In this regard, in conventional bur-typesurgical accessories, a bearing surface is typically provided on thecutting element proximally of the cutting head on which the bur isformed, which bearing surface serves to support the cutting element assame moves relative to the outer housing element and to compensate fortransversely-oriented forces which may occur during use of theaccessory. Further, it is desirable to provide a radial gap between thebur-type cutting head and the inner surface of the distal end of theouter housing element so as to prevent or at least minimize thegeneration of particles as a result of contact between the cutting headand the outer housing element. This type of contact can occur, forexample, when the cutting head is brought into contact with hard or bonytissue and as a result a lateral or transverse force is applied to thesurgical accessory as mentioned above. Conversely, in conventionalshaver surgical accessories in which the cutting windows of the outerhousing element and the inner cutting element cooperate with one anotherto sever tissue as the cutting element rotates relative to the outerhousing element, it is desirable to provide a very minimal radial gap (aradial gap which is much less than the radial gap provided in a bur-typesurgical accessory) between the distal ends of the inner cutting elementand the outer housing element so as to ensure that the proper scissoringaction between the windows occurs. Including both a hard-tissue treatingarea, such as a bur, and a soft-tissue treating area, such as ashaver-type window configuration, in a single surgical accessory was notbelieved possible prior to the development of the surgical accessorydisclosed herein, due to concerns relating to particle generation anddue to the substantially different radial gap requirements in the twotypes of surgical accessories as discussed above.

The surgical accessory 12 with its cutting head 104 which incorporatesboth a hard-tissue abrading area (first tissue-treating area 110) and asoft-tissue removing area (second tissue-treating area 119) maintainsthe small radial gap required to ensure proper cutting or scissoringaction between the cooperating windows 122 and 67 of the cutting element33 and the outer housing element 32, while at the same time prevents orat least minimizes particle generation and/or flaking bysurface-treating or hardening the cutting element 33 and the outerhousing element 32, and also by providing the lands 118 on the cuttinghead 104 at the first tissue-treating area 110, as discussed above.

FIGS. 13 and 14 illustrate a further embodiment of the surgicalaccessory which will now be described. Components of this embodimentwhich are similar or identical to components of the first-discussedembodiment will include the same reference numbers plus “200”, and adetailed description of all components will accordingly not be provided.As in the prior embodiment, the cutting head 304 is provided with twodifferent types of tissue-treating areas. The first tissue-treating area310 has an abrading surface or region configured as a bur, which issubstantially identical to the first tissue-treating area 110 and willtherefore not be described further. The second tissue-treating area 319includes a window 322 with a substantially smooth first cutting edge 323on one side thereof, and the opposite side of the window 322 disposed insubstantially facing and opposed relation with the first cutting edge323 defines a second cutting edge 324 which is provided with at leastone, and here a plurality, of teeth 325. It will be appreciated that thefirst cutting edge 323 may be provided in one embodiment with a tooth325A or teeth as shown in dotted lines in FIG. 13, and as discussedrelative to the embodiment of FIG. 5. The window 322 is formed so as tosubstantially follow the helical angle of the cutting surfaces andflutes of the first tissue-treating area 310. The narrow size of thewindow 322 of this embodiment serves to minimize vibration of thecutting element 33 during use. Further, forming the window 322 so as tosubstantially follow the helix of the cutting surfaces and flutes allowsa maximally-sized window for more efficient and effective tissueresection and removal. As in the prior embodiment, the wall thickness ofthe wall 308 of the cutting head 304 is of an increased dimension in thearea of the first tissue-treating area 310. Additionally, thisembodiment, depending on the intended use thereof, may be provided withlands 318 as shown in FIG. 14, or may alternatively be provided withrelief angles and flats (not shown here but see FIG. 11) in order toincrease the aggressiveness of the cutting head 304. Further, the secondcutting edge 324 may alternatively be non-toothed such that same ishelically-oriented but smooth, as shown in dotted lines in FIG. 13.

FIGS. 15 and 16 illustrate a further embodiment of the surgicalaccessory. Components of this embodiment which are similar or identicalto components of the first-discussed embodiment will include the samereference numbers plus “300”. This embodiment includes a cutting head404 having two different tissue-treating areas 410 and 419 located alongthe periphery thereof. The first tissue-treating area 410 includes anabrading region with a single cutting surface 415 and correspondingflute 417, which cutting surface 415 and flute 417 arehelically-oriented, but may alternatively extend linearly substantiallyparallel with the axis of the cutting head 404. The secondtissue-treating area 419 includes a window 422. The window 422 in thisembodiment includes a pair of opposed and facing cutting edges 423 and424 which are substantially smooth and extend substantially linearly andalso are substantially parallel with one another, and a distal cuttingedge 426 oriented transversely between distal ends of the cutting edges423 and 424. The distal cutting edge 426 in this embodiment issubstantially linear. Further, the window 422 here is non-toothed, butmay be provided with a tooth or a plurality of teeth on one or both ofthe cutting edges 423 and 424, and one example of a tooth provided onthe edge 424 is shown in dotted lines in FIG. 16.

FIGS. 17 and 18 illustrate a yet another embodiment, and componentsthereof which are similar or identical to components of thefirst-discussed embodiment will include the same reference numbers plus“400”. The cutting head 504 according to this embodiment comprises afirst tissue-treating area 510 with an abrading region including twocutting surfaces 515 and corresponding flutes 517 provided opposite thewindow 522 of the second tissue-treating area 519. Here, the surfaces515 and flutes 517 are helically-oriented, but may alternatively extendlinearly substantially parallel with the axis of the cutting head 504.Further, the window 522 here is non-toothed, but may be provided with atooth or a plurality of teeth on one or both of the edges 523 and 524,and one such tooth provided on the edge 524 is shown in dotted lines inFIG. 18.

FIGS. 19 and 20 illustrate the cutting head 404 located interiorly ofthe outer housing element 32. It will be appreciated that the embodimentdepicted in FIGS. 15-18 may be provided with lands similar to the lands118 as illustrated in FIG. 10, or alternatively may be provided withrelief angles and flats similar to angles C and flats 218 of theembodiment illustrated in FIG. 11. It will also be appreciated that anyof the embodiments described herein which include a helically orientedcutting surface (or surfaces) and flute (or flutes) may alternativelyinclude cutting features which extend not helically, but linearly or ina substantially straight manner longitudinally along the cutting headsubstantially parallel to, or at an angle relative to, the axis thereof.

FIGS. 21-24 illustrate a further embodiment of the surgical accessory,and components of this embodiment which are similar or identical tocomponents of the first-described embodiment will include the samereference numbers plus “500”, and a detailed description of allcomponents will not be provided. As in the earlier describedembodiments, the cutting head 604 of this embodiment incorporates twodifferent types of tissue-treating areas 610 and 619 disposed inspaced-relation with one another along the periphery of the cutting head604. The first tissue-treating area 610 of the cutting head 604incorporates an abrading region which in this embodiment is generallysimilar to a rasp, and includes a plurality of teeth 640. Each of theseteeth 640 at an outermost radial extent thereof defines an outerterminal edge 613, and each tooth 640 additionally includes a pair ofcutting surfaces or faces 615 on opposite sides of the correspondingterminal edge 613 and facing away from one another. The arrangement ofthe teeth 640 as shown allows a similar type of cutting action in boththe forward and reverse directions of rotation of the cutting head 604,which may be advantageous in that bone chips, for example duringshoulder surgery, can be directed away from the endoscopic camera 10C inboth right and left shoulder surgeries without sacrificing cuttingspeed. The second tissue-treating area 619 of this embodiment issubstantially identical to the second tissue-treating area 119 of thefirst-described embodiment and will not be described further here. Itwill be appreciated that the tissue-treating area 619 may be toothed ornon-toothed as described above relative to the area 119. Further, thisembodiment includes lands 618, which function similarly to the lands 118shown in the FIG. 10 embodiment.

FIGS. 25-29 illustrate a further embodiment of the surgical accessorywhich will now be described. Components of this embodiment which aresimilar or identical to components of the first-described embodimentwill include the same reference numbers plus “600”, and a detaileddescription of all components will accordingly not be provided. As inthe prior embodiments, the cutting head 704 of this embodiment isprovided with two different types of tissue-treating areas 710 and 719.In this embodiment, the first tissue-treating area 710 includes anabrading region in the form of abrasive particles 760. The abrasiveparticles 760, in the illustrated embodiment, are diamond grit particles760. The diamond grit particles 760 may be synthetic diamond, but mayalso be of natural diamond. In order to accommodate these particles 760,the wall 708 of the cutting head 704 defines therein an outwardlyopening recess 750 as best shown in FIG. 29, which recess 750 extendsarcuately about a portion of the cutting head 704 in a circumferentialdirection and also extends axially along the cutting head 704 along asubstantial portion of the length thereof. The recess 750 is definedalong a periphery thereof by substantially flat faces 751 formed alongthe wall 708. As shown in FIGS. 27 and 29, the recess 750 does notpenetrate radially through the wall 708, and instead terminates, in aradial direction, at an outwardly facing surface 752 of the wall 708which defines a bottom of the recess 750. The surface 752 adjoins eachof the faces 751 at lower terminal portions thereof, and the surface 752and faces 751 together provide the recess 750 with a shallow andoutwardly opening configuration.

The particles 760 are disposed within the recess 750 and are attached tothe wall 708 of the cutting head 704. In one embodiment, the wall 708 isconstructed of stainless steel, and the diamond grit particles 760 areattached to the wall 708 by use of a nickel plating 753. The use of thenickel plating 753 results in the diamond grit particles 760 beingbonded to the stainless steel wall 708 via co-deposition thatmechanically locks the particles 760 to the wall 708. The nickel plating753 is electrodeposited onto the wall 708, and the diamond gritparticles 760 are coated between about 50 and about 70% of their nominaldiameter.

The wall 708 is coated with the particles 760 by creating a steel blank,which is masked so that only the intended area of the wall 708 iscoated. The particles 760 and an initial nickel or nickel matrix layerare simultaneously co-deposited onto the blank in a nickelelectrodeposition bath. The bath includes a nickel electrolyte solutionand containers of diamond-grit particles submerged therein. The steelblank is positioned so that the surfaces that require coating areimmersed in the layer of diamond-grit particles. A small initial layerof nickel is deposited onto the non-masked exterior surface of the blankvia electrodeposition. This layer of nickel builds up around the diamondgrit particles that are touching the blank and mechanically tacks themto the wall 708 within the recess 750. After a relatively thin layer ofnickel has been built up on the wall 708, the part is removed from theelectrodeposition bath and placed into another nickel electrodepositionbath that does not contain any diamond particles. The electrodepositionprocess continues until the nickel layer has reached the desired depthto ensure the diamond-grit particles 760 are securely bonded to theblank. In this regard and as shown in FIG. 29, the depth of the recess750, the depth of the nickel plating layer 753 and the grit size of theparticles 760 are chosen so that the particles 760 do not protrudebeyond the outer diameter of the cutting head 704 in order to preventwear on the outer housing element (not shown here) inside which thecutting head 704 is located. For larger diameter cutting accessories,such as those with a 5.5 mm outer diameter, the particles 760 may have agrit size of less than or equal to D252. For smaller diameter cuttingaccessories, such as those with a 4.0 mm outer diameter, the particles760 may have a grit size of less than or equal to D151. Other grit sizeswhich may be utilized are D64, D76, and D107. The number included in theaforementioned grit sizes represents the nominal size of the diamondgrit in micrometers. The grit sizes discussed above are only examples,and other grit sizes may be utilized. It will be appreciated that theembodiment depicted in FIGS. 25-29 may include a land, for example inthe form of a strip which extends along the first tissue-treating area719, which land includes an outer radial surface having an outerdiameter which closely matches the inner diameter of the distal end ofthe outer housing tube so as to provide support between the cuttingelement and the outer housing element.

The second tissue-treating area 719 of this embodiment is substantiallyidentical to the second tissue-treating area 119 of the first-describedembodiment and will not be described further here.

FIGS. 30-35 illustrate a further embodiment of the surgical accessorywhich will now be described. Components of this embodiment which aresimilar or identical to components of the first-described embodimentwill include the same reference numbers plus “700”, and a detaileddescription of all components will accordingly not be provided. As inthe first-described embodiment, the cutting head 804 is provided withtwo different types of tissue-treating areas. The first area 810includes an abrading region having a bur configuration incorporating afluted region with a plurality of cutting surfaces 815 and flutes 817oriented in an alternating manner with one another along thecircumference of the cutting head 804. The first tissue-treating area810 of this embodiment has the flutes 817 and cutting surfaces 815extending straight or linearly and substantially parallel with oneanother and with the axis 814 along a majority of the longitudinalextent of the distal end portion 807 of the cutting head 804. Each ofthe cutting surfaces 815 terminates at a cutting edge 813 which definesthe radially outermost extent of the respective cutting surface 815. Thecutting edges 813 extend in the proximal to distal direction andterminate adjacent the tip 816 of the distal end portion 807, as shownin FIGS. 30, 33 and 34. In this embodiment, the edges 813 terminateproximally of the tip 816, which effectively creates a bearing surface816A at the tip 816, as in the embodiment shown in FIG. 9. It will beappreciated that the cutting surfaces 815 and the flutes 817 mayalternatively be helically oriented as shown in dotted lines in FIG. 33.

In this embodiment, and as shown in FIGS. 30 and 34, the portions of thewall 808 of the cutting head 804 located between neighboring pairs ofcutting surfaces 815 are provided with lands 818 as in the embodimentshown in FIG. 10, and serve to minimize wear on the interior surface ofthe housing tube of the outer housing element 32 due to movement of thecutting element relative thereto.

The cutting head 804, in an area spaced circumferentially from the firsttissue-treating area 810, is provided with a second tissue-treating area819 including a window 822 formed as an elongated opening in the cuttinghead 804. In this embodiment, the window 822 opens both sidewardly (ortransversely) relative to the axis 814 and also distally, andcommunicates with the interior 805 of the cutting head 804. Oppositelongitudinal sides of the window 822 define first and second cuttingedges 823 and 824 located in substantially opposed, substantially facingand sidewardly (or circumferentially-spaced) relation with one another.The cutting edges 823 and 824 in this variation are substantially linearand parallel with one another, and are non-toothed. It will beappreciated that the window 822 may also be toothed along one or both ofthe edges 823 or 824. An example of one such tooth 825 provided on theedge 823 is shown in dotted lines in FIG. 31.

As shown in FIGS. 31 and 34, the window 822 additionally includes adistal cutting edge 826, which in this embodiment is substantiallystraight or linear and extends between and interconnects the first andsecond cutting edges 823 and 824.

The window 822 may be provided with varying geometries suitable for thetype of tissue-treatment the cutting head 804 is intended to achieve. Inthis regard, if the window 822 is provided with a tooth or teeth 825,same may be provided with an internal shear angle based on the intendedcutting action, as described above. Also, as shown in FIG. 35, the wall808 in this embodiment has a thickness dimension 808A which is greaterin the area of the first tissue-treating area 810 as compared to thethickness of the wall 808 in the region of the second tissue-treatingarea 819 which provides the cutting head 804 with increased rigidity andstructural integrity to permit the formation of the cutting surfaces 815and flutes 817. As also shown in FIG. 35, the cutting head 804 includesfirst and second bores 811A and 811B, which bore 811B is radially offsetfrom the central axis 814 to provide the increased wall thickness of thewall 808 adjacent the first tissue-treating area 810. Alternatively, thesecond bore 811B may be provided with a non-circular configuration asshown in FIG. 10, with its axis aligned or offset from the axis, with aD-configuration, or with the configuration shown in FIG. 11. Stillfurther, as an alternative to providing two bores within the cuttinghead 804, a single bore of a constant diameter can be provided in thecutting head 804, which single bore is of a diameter small enough toallow both a cutting window and flutes to be formed on the cutting head804.

The embodiment illustrated in FIGS. 30-35 is useful for various types ofsurgery, such as shoulder, knee or hip surgery, but may be particularlysuited for shoulder surgery. More specifically, it is often desirable inshoulder surgery to provide equal cutting action in both (opposite)directions of rotation of the cutting head 808, and the straight andparallel first and second cutting edges 823 and 824, along with thestraight and parallel cutting edges 813 on opposite sides of eachrespective flute 817, allow for such balanced cutting or resectionaction.

FIGS. 36-42 illustrate another embodiment of the cutting accessory.Components of this embodiment which are similar or identical tocomponents of the first-discussed embodiment will include the samereference numbers plus “800”, and a detailed description of allcomponents will therefore not be provided. The cutting head 904according to this embodiment is provided with multiple tissue-treatingareas. In this regard, a pair of first tissue-treating areas 910 and apair of second tissue-treating areas 919 are provided on the cuttinghead 904, and these areas 910 and 919 are arranged in an alternatingmanner with one another along the periphery or circumference of thecutting head 904. Each of the first areas 910 includes an abradingregion which is fluted and has a plurality of cutting surfaces 915 (andrespective cutting edges 913) and flutes 917 oriented in an alternatingmanner with one another along the circumference of the cutting head 804.The flutes 917 and cutting surfaces 915 may be straight andsubstantially parallel with one another as shown or may behelically-oriented as shown in dotted lines in FIG. 39, based on thedesired type of resecting action. The cutting edges 913 extend in theproximal to distal direction and terminate adjacent the tip 916 of thedistal end portion 907. In this embodiment, the edges 913 extend close(in the distal direction) to the tip 916, which maximizes the area ofthe tissue-treating areas 910 available for use during surgery. Further,in this variation, and as best shown in FIG. 40, the portions of thewall 908 of the cutting head 904 located between neighboring pairs ofcutting surfaces 915 are provided with lands 918 which serve to minimizewear on the outer housing element caused by movement of the cutting head904 relative thereto.

Each of the window-type second tissue-treating areas 919 includes awindow 922 formed as an elongated opening in the cutting head 904. Eachwindow 922 opens both sidewardly (or transversely) relative to the axis914 and distally, and communicates with the interior 905 of the cuttinghead 904. Opposite longitudinal sides of each window 922 define firstand second cutting edges 923 and 924 located in substantially opposedand facing relation with one another. Each of the windows 922additionally includes a distal cutting edge 926, which in thisembodiment is substantially straight or linear and extends between andinterconnects the corresponding first and second cutting edges 923 and924.

Each of the windows 922 may be provided with varying geometries suitablefor the type of tissue-treatment the cutting head 904 is intended toachieve. In this regard, the cutting edges 923 and 924 in this variationare substantially linear and parallel with one another, and arenon-toothed. However, it will be appreciated that the windows 922 may betoothed along one or both edges thereof, and by way of example aplurality of teeth 925 are shown along the edge 923 in dotted lines inFIG. 37. If the window (or windows) 922 is provided with a tooth orteeth 925, same may be provided with an internal shear angle based onthe intended cutting action, as described previously.

With reference to FIGS. 38, 41 and 42, the cutting head 904 includesfirst and second bores 911A and 911B which are centered on the axis 914.The first bore 911A as illustrated is sized to permit attachment of thecutting head 904 to the drive shaft 88. The second bore 911B is of alesser diameter than the first bore 911A and results in the formation ofa sufficient wall thickness at each of the first tissue-treating areas910 to provide sufficient structural rigidity at these areas. Morespecifically, the wall 908 of the cutting head 904 at the areas 910 hasa thickness dimension 908A which is substantially constant in theregions circumferentially between the windows 922 and proximally of therespective windows 922.

The embodiment depicted in FIGS. 36-42 includes a bearing surface 916Aat the distal end 916 of the cutting head 904 which helps to support thecutting head 904 during movement relative to the outer housing element.If additional support for the cutting head 904 is desirable ornecessary, the extent to which the windows 922 extend in the distaldirection can be reduced in order to provide a larger bearing surface916B, as shown in dotted lines in FIGS. 36 and 37. Additionally, withreference to FIGS. 36 and 40, the portions of the wall 908 of thecutting head 904 located between neighboring pairs of cutting surfaces915 are provided with lands 918 which serve to minimize wear on theinterior surface of the housing tube of the outer housing element 32 dueto movement of the cutting head 904 relative thereto.

FIGS. 43-47 illustrate a further embodiment of the cutting accessorywhich will now be described. This embodiment includes a housing tubedistal end 966 which is a variation of the distal end 66 of the housingtube 64 described previously, which distal end 966 can be utilized withany of the previously described cutting heads 104, 204, 304, 404, 504,604, 704, 804 and 904. Additionally, FIGS. 46 and 47 illustrate afurther embodiment of a cutting head 1004 assembled with the embodimentof the housing tube distal end 966 shown in FIGS. 43-45, which cuttinghead 1004 is similar to the cutting head 104 illustrated in FIGS. 5-12.It will be appreciated that the cutting head 1004 shown in FIGS. 46 and47 may alternatively be utilized with a housing tube including thewindowed distal end 66 described previously. Components depicted inFIGS. 43-47 which are similar or identical to components of thefirst-described embodiment will include the same reference numbers plus“900”, and a detailed description of all components will accordingly notbe provided.

The distal end 966 of the housing tube according to this variation iscut or formed to define a window 967 having an annular edge 968, whichwindow 967 opens both sidewardly (or transversely) relative to the axis931 and also opens distally. In forming the window 967, the wall of thedistal end 966 of the housing tube is cut away or removed along thesides, and also distally, to a greater degree as compared to the window67 formed on the distal end 66, which provides the distal end 966 with ascoop-like or spoon-shaped configuration. More specifically, and withreference to FIGS. 44, 46 and 47, the edge 968 of the distal end 966 ofthe outer housing element is arcuately curved so as to open upwardly onopposite sides of the distal end 966, and the edge 968 is also formedsuch that the distal end 966 terminates at a slightly upwardlyprojecting nose 968C. The edge 968 includes a pair of cutting edges 968Aand 968B oriented in substantially opposed relation with one another andwhich are spaced circumferentially (or sidewardly-spaced) from oneanother along the distal end 966 of the housing tube. The annular edge968, with its cutting edges 968A and 968B and nose 968C, is formed as aresult of a cutting operation performed on the distal end 966 of thehousing tube. The edges 968A and 968B effectively define free andcircumferentially extending terminal edges of the housing tube so as toform respective sides of the window 967.

The cutting head 1004 of this embodiment is shown located within thedistal end 966 of the outer housing element in FIGS. 46 and 47. Thecutting head 1004 includes first and second tissue-treating areas 1010and 1019. In this embodiment, the tissue treating area 1010 of thecutting head 1004 includes an abrading region with cutting edges 1013,cutting surfaces 1015 and flutes 1017 which extend further distallyalong the cutting head 1004 as compared to the edges 113, surfaces 115and flutes 117 of the embodiment shown in FIGS. 5-9. This configurationof the cutting head 1004, in combination with the reduced-area ofcoverage provided by the scoop-shaped distal end 966 of the outerhousing element, allows a greater portion of the cutting head 1004 to beused to treat hard tissue. In this regard, this embodiment frees upgreater regions of the tissue-treating area 1010 of the cutting head1004 so that hard tissue can be resected even at the very end of thecutting head 1004. The cutting head 1004 of FIGS. 46 and 47 may havehelically-oriented flutes 1017 or may alternatively include straight orlinear flutes 1017.

FIGS. 48-51 illustrate a further embodiment of the surgical cuttingaccessory. This embodiment includes a distal end 1066 of the housingtube which is a further variation of the distal end 66 describedpreviously, which distal end 1066 can be utilized with any of thepreviously described cutting heads 104, 204, 304, 404, 504, 604, 704,804, 904 and 1004. For illustrative purposes, FIGS. 50 and 51 depict thecutting head 1004 shown in FIGS. 46 and 47 assembled with the variationof the housing tube distal end 1066 shown in FIGS. 48 and 49. Componentsshown in FIGS. 48-51 which are similar or identical to components of thefirst-discussed embodiment will include the same reference numbers plus“1000”, and a detailed description of all components will accordinglynot be provided.

The distal end 1066 of the housing tube according to this variation iscut or formed to define a window 1067 having an edge 1068, which window1067 opens both sidewardly (or transversely) relative to the axis 1031,and also opens distally (axially) to a greater extent as compared to thewindow 967 shown in the embodiment depicted in FIG. 43. In forming thewindow 1067, the wall of the distal end 1066 of the housing tube is cutto form a distal edge 1070 having an edge surface 1071 orientedperpendicular to the axis 1031, and so as to form an arcuate edge 1068including a pair of sidewardly-spaced and upwardly-opening recesses orvalleys 1072 which respectively adjoin to opposite upper ends of theedge surface 1071 and at these junctures define respective tooth-likestructures or projections 1073 which serve as catches for tissue.

The cutting head 1004 shown in FIGS. 46 and 47 is shown assembled withinthe distal end 1066 of the outer housing element in FIGS. 49 and 50, asmentioned above. With reference to FIG. 50, this cutting head 1004projects a short distance axially beyond the distal edge 1070 of thedistal end 1066 of the housing tube. The reduced-area of coverageprovided by the truncated and recessed distal end 1066 of the outerhousing element allows a greater portion of the cutting head 1004 (orany of the previously-described cutting heads 104, 204, 304, 404, 504,604, 704, 804 and 904) to be used to treat tissue, and effectively freesup greater regions of the tissue-treating area 1010 of the cutting head1004 so that hard tissue can be resected even at the very end of thecutting head 1004. Further, the tooth-like structures 1073 of the distalend 1066 of the outer housing element serve to prevent (or at leastminimize) soft tissue from sliding off of the end of the accessoryduring rotation of the cutting head 1004, and thus serve astissue-catches.

FIG. 52 illustrates a variation of the drive shaft 88 of thefirst-described embodiment, and components depicted in FIG. 52 which aresimilar or identical to components of the first-described embodimentwill include the same reference numbers plus “1100”, and a detaileddescription of all components will accordingly not be provided. Thedrive shaft 1188 shown in FIG. 52 is a non-tubular solid shaft, whichmay be rigid or flexible. In this variation, the proximal end of thedrive shaft 1188 (not shown) is fixed to the hub of the cutting elementas described previously, and the distal end 1191 of the drive shaft 1188is fixed to an inner surface of the wall 1208 of the cutting head 1204.It will be understood that the cutting head 1204 shown in thefragmentary view of FIG. 52 is intended to represent any of thepreviously-described cutting heads 104, 204, 304, 404, 504, 604, 704,804, 904 and 1004 as the drive shaft 1188 may be utilized with any ofthese cutting heads, and that the distal end 1166 of the outer housingelement shown in this figure is intended to represent any of thepreviously-described distal ends 66, 966 and 1066. As shown by thedirectional arrows in FIG. 52, in this embodiment suction is drawnthrough the window 1167 defined by the edge 1168 of the distal end ofthe outer housing element and the window 1222 of the secondtissue-treating area of the cutting head 1204 when these windows 1167and 1222 are aligned with one another during rotation of the cuttinghead 1204 relative to the outer housing element, and then continues onin the proximal direction through the outer housing element to thehandpiece 11.

FIGS. 53-64 illustrate a further embodiment of the surgical accessorywhich will now be described. Components of this embodiment which aresimilar or identical to components of the first-described embodimentwill include the same reference numbers plus “1200”, and a detaileddescription of all components will not be provided. As in the priorembodiments, the cutting head 1304 includes different types of tissuetreating areas 1310 and 1319. The first area 1310 has an abrading regionwith a bur configuration incorporating a fluted region with a pluralityof cutting surfaces 1315 and flutes 1317 oriented in an alternatingmanner with one another along the circumference of the cutting head1304. The first tissue-treating area 1310 in this embodiment has theflutes 1317 and cutting surfaces 1315 extending helically along amajority of the longitudinal extent of the distal end portion 1307 ofthe cutting head 1304. Further, the cutting edges 1313 of the respectivecutting surfaces 1315 here extend in the proximal to distal directionand terminate proximally of the tip 1316 of the distal end portion 1307,as best shown in FIG. 57, to allow formation of the bearing surface1316A. It will be appreciated that the cutting surfaces 1315 and theflutes 1317 may alternatively be straight or linear as shown in dottedlines in FIG. 55.

As shown in FIG. 57, the portions of the wall 1308 of the cutting head1304 located between neighboring pairs of cutting surfaces 1315 areprovided with lands 1318, which lands 118 serve to minimize wear on theinterior surface of the outer housing element, as discussed previously.

The cutting head 1304, in an area spaced circumferentially from thefirst tissue-treating area 1310, is provided with a secondtissue-treating area 1319 including a window 1322 formed as an elongatedopening in the cutting head 1304. The window 1322 in this embodimentopens both sidewardly (transversely) and distally (axially), andcommunicates with the interior 1305 of the cutting head 1304. Oppositelongitudinal sides of the window 1322 define first and second cuttingedges 1323 and 1324 located in substantially opposed, substantiallyfacing and sidewardly (or circumferentially-spaced) relation with oneanother. Each of the cutting edges 1323 and 1324 in this embodiment aretoothed, and here a plurality of teeth 1325 are provided along each ofthe edges 1323 and 1324. Further, in this embodiment, each edge includesthe same number of teeth 1325. It will be appreciated that a greater orlesser number of teeth 1325 than that shown may be provided along eachedge 1323, 1324. Further, the edges 1323 and 1324 may not include thesame number of teeth 1325. Additionally, only one of the edges 1323 or1324 may be toothed, and the other edge may be non-toothed.

With reference to FIG. 59, the cutting window 1322 in this embodiment isprovided with a geometry, and specifically a shear angle, whichmaximizes the tissue-treating ability of the cutting head 1304. Shearangle in this context is intended to refer to the opening angle of thewindow 1322 which is determined during the cutting process used to formthe window 1322. In this regard, the edge of the cutting head 1304 whichdefines the window 1322 may be cut so as to provide the teeth 1325 witha negative internal shear angle which is less than zero degrees. Thisnegative shear angle, when applied to cutting edges such as the teeth1325, increases the likelihood that tissue will be scooped into thecutting window 1322, thereby increasing the consumption rate of theaccessory. In the illustrated embodiment, the internal faces of theteeth 1325 are provided with an internal shear angle X, which angle X isless than zero degrees. In one embodiment, it may only be necessary toprovide the tips of the teeth 1325 with this angle X, and not the entireinternal face of the tooth 1325 (from root to tip). Further, it may bedesirable to provide the teeth 1325 provided along the edge 1323 of thewindow 1322 of the cutting head 1304 with a larger size at their rootsas compared to the teeth 1325 along the opposite edge 1324, so thatthese teeth are capable of withstanding the impact of hard tissuethereon (since the teeth 1325 along the edge 1323 are oriented in thehard-tissue resecting direction as determined by the rake direction ofthe first tissue-treating area 1310).

As shown in FIGS. 58 and 59, the wall 1308 of the cutting head 1304 hasa thickness dimension 1308A which is greater in the area of the firsttissue-treating area 1310 as compared to the thickness of the wall 1308in the region of the second tissue-treating area 1319, which providesthe cutting head 1304 with increased rigidity and structural integrityto permit the formation of the cutting surfaces 1315 and flutes 1317.Additionally, the cutting head 1304 includes first and second bores1311A and 1311B, which bore 1311B is radially offset from the centralaxis 1314 to provide the increased wall thickness of the wall 1308adjacent the first tissue-treating area 1310. The second bore 1311B mayalternatively be provided with a non-circular configuration as shown inFIG. 10, with its axis aligned or offset from the axis 1314, with aD-configuration, or with the configuration shown in FIG. 11. As analternative to two bores provided within the cutting head 1304, a singlebore of a diameter small enough to allow both a cutting window andflutes to be formed in the cutting head 1304.

FIGS. 60-64 illustrate the cutting head 1304 assembled within an outerhousing element 1232. In this embodiment of the cutting head 1304, thewindow 1322 is of a longitudinal length which is greater than thelongitudinal length of the window 1267 formed in the distal end 1266 ofthe outer housing element 1232. In this regard, when the cutting head1304 is located within the outer housing element 1232, the mostproximally-located part 1322A of the window 1322 of the cutting head1304 is spaced proximally of the most proximal edge 1267A of the outerhousing element window 1267. In some situations, tissue can snag or getcaught in areas adjacent the proximal part 1322A of the window 1322, andthis configuration may serve to minimize snagging or catching of tissue,which can potentially cause clogging of the accessory. It will beappreciated that the preceding embodiments of the surgical accessorydescribed herein may incorporate the arrangement of the windows 1267 and1322 of the outer housing element 1232 and the cutting head 1304depicted in FIGS. 60-64. That is, the most proximally-located edge ofthe windows of the respective cutting heads described previously may bespaced proximally of the most proximally-located edge of the windows ofthe respective outer housing elements described previously.

Examples of Uses of the Systems and Methods in Combination with MedicalImaging of Tissue in the Surgical Site

In various embodiments, the systems and methods described herein may beused in combination with medical imaging of tissue in the surgical siteto facilitate the resection, removal or cutting of tissue and othersurgical steps that may need to be performed. In various embodiments,methods employing medical imaging of the tissue (e.g., connective softtissue or body structure, or connective hard tissue or body structure)alone or in combination with the systems and methods for resection,removal or cutting of tissue described in the various embodiments may beused in assessment of the tissue, diagnosis of the tissue or acombination thereof during pre-surgical intervention/examination, duringsurgical intervention/examination, or during post-surgicalintervention/examination. Examples of various optical modalities in suchapplications include white light imaging, fluorescence imaging (e.g.,using endogenous and exogenous fluorophores), or a combination thereof.The medical imaging may be performed in the visible region, nearinfrared region, or a combination thereof. In an embodiment comprisingfluorescence medical imaging applications, an imaging agent for use incombination with the methods, systems, uses and kits described herein isa fluorescence imaging agent such as, for example, indocyanine green(ICG) dye. The fluorescence imaging agent (e.g., ICG) may beadministered to the subject as a bolus injection (e.g., into a vein oran artery) in a concentration suitable for imaging such that the boluscirculates in the vasculature and traverses the microvasculature. Inother embodiments in which multiple fluorescence imaging agents areused, such agents may be administered simultaneously, e.g. in a singlebolus, or sequentially in separate boluses. In some embodiments, thefluorescence imaging agent may be administered by a catheter. In certainembodiments, the fluorescence imaging agent may be administered lessthan an hour in advance of performing the measurement of signalintensity arising from the fluorescence imaging agent. For example, thefluorescence imaging agent may be administered to the subject less than30 minutes in advance of the measurement. In yet other embodiments, thefluorescence imaging agent may be administered at least 30 seconds inadvance of performing the measurement. In still other embodiments, thefluorescence imaging agent may be administered contemporaneously withperforming the measurement.

In some embodiments, the fluorescence imaging agent may be administeredin various concentrations to achieve a desired circulating concentrationin the blood or in other body tissue or fluid into which thefluorescence agent is administered or which it perfuses. For example, inembodiments where the fluorescence imaging agent is ICG, it may beadministered at a concentration of about 2.5 mg/mL to achieve acirculating concentration of about 5 μM to about 10 μM in blood. Invarious embodiments, the upper concentration limit for theadministration of the fluorescence imaging agent is the concentration atwhich the fluorescence imaging agent becomes clinically toxic incirculating blood or other body tissue or fluid, and the lowerconcentration limit is the instrumental limit for acquiring the signalintensity data arising from the fluorescence imaging agent circulatingwith blood or in other body tissue or fluid to detect the fluorescenceimaging agent. In various other embodiments, the upper concentrationlimit for the administration of the fluorescence imaging agent is theconcentration at which the fluorescence imaging agent becomesself-quenching. For example, the circulating concentration of ICG mayrange from about 2 μM to about 10 mM. Thus, in one aspect, the methodsdescribed herein may comprise the step of administration of the imagingagent (e.g., a fluorescence imaging agent) to the subject andacquisition of the signal intensity data (e.g., video) prior toprocessing the signal intensity data where desired. In another aspect,the method may exclude any step of administering the imaging agent tothe subject.

In an embodiment, a suitable fluorescence imaging agent for use influorescence imaging applications alone or in combination with otherimaging to generate fluorescence image data of the tissue or bodystructure in the surgical site to be or being treated using the systemsand methods described herein is an imaging agent which can circulatewith the blood (e.g., a fluorescence dye which can circulate with, forexample, a component of the blood such as lipoproteins or serum plasmain the blood) and transit vasculature of the tissue (i.e., large vesselsand microvasculature), and from which a signal intensity arises when theimaging agent is exposed to appropriate light energy (e.g., excitationlight energy, or absorption light energy). In some variations, thefluorescence imaging agent comprises a fluorescence dye, an analoguethereof, a derivative thereof, or a combination of these. A fluorescencedye includes any non-toxic fluorescence dye. In certain embodiments, thefluorescence dye emits fluorescence in the near-infrared spectrum. Incertain embodiments, the fluorescence dye is or comprises atricarbocyanine dye. In certain embodiments, the fluorescence dye is orcomprises indocyanine green (ICG), methylene blue, or a combinationthereof. In other embodiments, the fluorescence dye is or comprisesfluorescein isothiocyanate, rhodamine, phycoerythrin, phycocyanin,allophycocyanin, o-phthaldehyde, fluorescamine, rose Bengal, trypanblue, fluoro-gold, or a combination thereof, excitable using excitationlight wavelengths appropriate to each dye. In some embodiments, ananalogue or a derivative of the fluorescence dye may be used. Forexample, a fluorescence dye analog or a derivative includes afluorescence dye that has been chemically modified, but still retainsits ability to fluoresce when exposed to light energy of an appropriatewavelength. In yet other embodiments, a fluorescence dye is any dye andderivatives thereof which facilitates imaging tissues including bonetissue, cartilage tissue, muscle tissue (e.g., tendons) or a combinationthereof.

In an embodiment, the fluorescence imaging agent may be provided as alyophilized powder, solid, or liquid (e.g., in a kit with the systemsdescribed herein or further with an imaging system used in combinationwith the systems described herein). In certain embodiments, thefluorescence imaging agent may be provided in a vial (e.g., a sterilevial), which may permit reconstitution to a suitable concentration byadministering a sterile fluid with a sterile syringe for use as a kitwith the systems and methods described herein as noted above.Reconstitution may be performed using any appropriate carrier ordiluent. For example, the fluorescence imaging agent may bereconstituted with an aqueous diluent immediately before administration.In various embodiments, any diluent or carrier which will maintain thefluorescence imaging agent in solution may be used. As an example, ICGmay be reconstituted with water. In some embodiments, once thefluorescence imaging agent is reconstituted, it may be mixed withadditional diluents and carriers. In some embodiments, the fluorescenceimaging agent may be conjugated to another molecule, such as a protein,a peptide, an amino acid, a synthetic polymer, or a sugar, for exampleto enhance solubility, stability, imaging properties, or a combinationthereof. Additional buffering agents may optionally be added includingTris, HCl, NaOH, phosphate buffer, and/or HEPES.

A person of skill in the art will appreciate that, although afluorescence imaging agent was described above in detail, other imagingagents may be used in connection with the systems, methods, andtechniques described herein, depending on the optical imaging modalityand the type of tissue(s) to be imaged.

In some variations, the fluorescence imaging agent used in combinationwith the methods, systems, uses and kits described herein may be usedfor blood flow imaging, tissue perfusion imaging, or a combinationthereof, or to image tissue or a body structure (e.g., anatomy) (e.g.,tissues of the joints and surrounding tissues in the surgical site)which may performed during an invasive surgical procedure, a minimallyinvasive surgical procedure, or a non-invasive surgical procedure incombination with invasive and minimally invasive procedures.

In various embodiments, the methods, systems, uses, fluorescence agentsand kits may be used for tissue perfusion imaging. Tissue perfusionrelates to the microcirculatory flow of blood per unit tissue volume inwhich oxygen and nutrients are provided to and waste is removed from thecapillary bed of the tissue being perfused. Tissue perfusion is aphenomenon related to but also distinct from blood flow in vessels.Quantified blood flow through blood vessels may be expressed in termsthat define flow (i.e., volume/time), or that define speed (i.e.,distance/time). Tissue blood perfusion defines movement of blood throughmicro-vasculature, such as arterioles, capillaries, or venules, within atissue volume. Quantified tissue blood perfusion may be expressed interms of blood flow through tissue volume, namely, that of bloodvolume/time/tissue volume (or tissue mass). Perfusion is associated withnutritive blood vessels (e.g., micro-vessels known as capillaries) thatcomprise the vessels associated with exchange of metabolites betweenblood and tissue, rather than larger-diameter non-nutritive vessels.

An embodiment includes a kit for imaging tissue in a surgical site, withthe kit comprising a fluorescence imaging agent and the system andmethods described herein.

While the present disclosure has been illustrated and described inconnection with various embodiments shown and described in detail, it isnot intended to be limited to the details shown, since variousmodifications and structural changes may be made without departing inany way from the scope of the present disclosure. Various modificationsof form, arrangement of components, steps, details and order ofoperations of the embodiments illustrated, as well as other embodimentsof the disclosure may be made without departing in any way from thescope of the present disclosure, and will be apparent to a person ofskill in the art upon reference to this description. It is thereforecontemplated that the appended claims will cover such modifications andembodiments as they fall within the true scope of the disclosure. Forthe purpose of clarity and a concise description features are describedherein as part of the same or separate embodiments, however, it will beappreciated that the scope of the disclosure includes embodiments havingcombinations of all or some of the features described. For the terms“for example” and “such as,” and grammatical equivalences thereof, thephrase “and without limitation” is understood to follow unlessexplicitly stated otherwise. As used herein, the singular forms “a”,“an”, and “the” include plural referents unless the context clearlydictates otherwise.

What is claimed is:
 1. A surgical accessory comprising: a cuttingelement having a proximal end, a distal end spaced therefrom and acutting head disposed at said distal end and defining a centrallongitudinal axis, said cutting head comprising: a wall defining ahollow interior portion within said cutting head; first and secondtissue-treating areas circumferentially spaced from one another along anouter peripheral area of said wall of said cutting head, said firsttissue-treating area and said second tissue-treating area beingconfigured differently from one another to provide said cutting headwith both hard and soft tissue-treating action, said firsttissue-treating area comprising a first region, the first region beingone of a fluted region or an abrading region, a first inner surface ofthe wall in the first region being a first distance from the centrallongitudinal axis, said second tissue-treating area comprising a secondregion, the second region being non-fluted and comprising a windowextending through said wall for communication with said hollow interiorportion, a second inner surface of the wall in the second region being asecond distance from the central longitudinal axis, the second distancebeing greater than the first distance, said wall having a pair of edgesconfigured to cut tissue and disposed in opposed and spaced relationfrom one another at said outer peripheral area, said edges respectivelydefining substantially opposite sides of said window and forming part ofsaid second tissue-treating area.
 2. The surgical accessory of claim 1,wherein said first region comprises a fluted region including a cuttingsurface and a flute each extending longitudinally along said outerperipheral area of said cutting head.
 3. The surgical accessory of claim1, wherein said wall of said cutting head at an area corresponding tosaid first tissue-treating area has a greater thickness than a thicknessof said wall at respective regions of said wall disposed adjacent saidedges of said second tissue-treating area.
 4. The surgical accessory ofclaim 3, wherein the thickness of the wall tapers in a circumferentialdirection from the first tissue-treating area towards the secondtissue-treating area.
 5. The surgical accessory of claim 4, wherein thecutting head has a single outer radius around an entirety of acircumference of the cutting head.
 6. The surgical accessory of claim 1,wherein the window has a length between a first end to a second end, thefirst end positioned more proximally than the second end, the first enddefined by a point of convergence between the opposite edges and thesecond end defined by an arcuate edge continuous between the oppositeedges.
 7. The surgical accessory of claim 1, wherein at least part of afirst edge of the pair of edges is parallel to an adjacent flute of thefirst tissue-treating area and both the first edge and the adjacentflute are helically oriented.
 8. The surgical accessory of claim 1,wherein the cutting head has a circumferential dimension and the windowencompasses less than half of the circumferential dimension.
 9. Asurgical accessory for treating a first tissue type having a firsthardness and for treating a second tissue type having a second hardnessless than the first hardness, said surgical accessory comprising: acutting element comprising: a proximal end; a distal end spacedtherefrom; and a cutting head disposed at said distal end and defining acentral longitudinal axis; said cutting head comprising: a wall defininga hollow interior portion within said cutting head; an outer peripheralarea formed on said wall, said outer peripheral area extending about thecentral longitudinal axis; and first and second tissue-treating areascircumferentially spaced from one another along the outer peripheralarea, said first tissue-treating area and said second tissue-treatingarea being configured differently from one another to provide saidcutting head with different types of tissue-treating action, said firsttissue-treating area comprising a first region configured for abradingthe first tissue type, said first region extending along a portion ofthe total of the outer peripheral area of said cutting head, a firstinner surface of the wall in the first region being a first distancefrom the central longitudinal axis, said second tissue-treating areacomprising a second region configured for treating the second tissuetype, a second inner surface of the wall in the second region being asecond distance from the central longitudinal axis, the second distancebeing greater than the first distance.
 10. The surgical accessory ofclaim 9, wherein said second region of said second tissue-treating areacomprising a window extending through said wall for communication withsaid hollow interior portion, said wall having a pair of edgesconfigured to cut tissue and disposed in opposed and spaced relationwith one another at said outer peripheral area, said edges respectivelydefining substantially opposite sides of said window.
 11. The surgicalaccessory of claim 10, further comprising an outer housing elementhaving a proximal end and a distal end spaced therefrom, said distal enddefining a window including a pair of edges configured to cut tissue anddisposed in opposed and spaced relation with one another, said cuttinghead being disposed within said distal end of said outer housing elementsuch that said edges of said window of said cutting head are disposed tocreate a scissoring action with said edges of said window of said outerhousing element to treat tissue located adjacent said windows duringmovement of said cutting head relative to said outer housing element.12. The surgical accessory of claim 11, wherein said wall is tubular inshape and extends circumferentially about the longitudinal axis andterminates at the respective said edges of said second tissue-treatingarea such that said edges thereof define free terminal edges of saidwall with said window being disposed therebetween.
 13. The surgicalaccessory of claim 10, wherein said wall of said cutting head at an areacorresponding to said first tissue-treating area has a greater thicknessthan a thickness of said wall at said second tissue-treating area. 14.The surgical accessory of claim 10, wherein said first tissue-treatingarea extends along a substantial circumferential portion of said outerperipheral area of said cutting head and comprises a solid andnon-windowed portion of said wall which is not in fluid communicationwith said hollow interior.
 15. The surgical accessory of claim 10,wherein one or both of said edges of said second tissue-treating areacomprises at least one tooth.
 16. The surgical accessory of claim 15,wherein the pair of edges of the second tissue-treating area include afirst edge with at least one tooth and a second edge with at least onetooth, the first edge having a first quantity of teeth and the secondedge having a second quantity of teeth different from the firstquantity.
 17. The surgical accessory of claim 15, wherein the pair ofedges of the second tissue treating area include a first edge with atleast one tooth of a first shape and a second edge with at least onetooth of a second shape different from the first shape.
 18. The surgicalaccessory of claim 10, wherein the window is asymmetric about thecentral longitudinal axis.
 19. The surgical accessory of claim 10,wherein the pair of edges includes an edge with a plurality of teethalong at least a portion of the edge, the portion being located a firstdistance from a distal end of the window and a second distance from aproximal end of the window, the first distance being less than thesecond distance.
 20. The surgical accessory of claim 9, wherein saidfirst region of said first tissue-treating area comprises a flutedregion including a cutting surface and a flute each extendinglongitudinally along said outer peripheral area of said cutting head.21. A surgical tool system comprising: a surgical accessory comprising:an outer housing assembly including a hub at a proximal end thereof andan elongate and tubular housing element having a proximal end fixed tosaid hub and a distal end spaced therefrom, said distal end defining ahousing element window, said housing element window being definedpartially by a pair of edges of said housing element configured to cuttissue and disposed in spaced relation from one another along aperiphery of said distal end; and a cutting element assembly forremoving a first tissue type having a first hardness and for removing asecond tissue type having a second hardness less than the firsthardness, said cutting element assembly including a hub at a proximalend thereof and a drive shaft disposed within said housing element formovement relative thereto, said drive shaft having a proximal end fixedto said hub of said cutting element assembly and a distal end spacedfrom said proximal end of said drive shaft, said cutting elementassembly further comprising: a cutting head defining a centrallongitudinal axis, said cutting head having a wall defining a hollowinterior portion and an exterior portion and comprising first and secondtissue-treating areas circumferentially spaced from one another alongsaid exterior portion of said cutting head, said first tissue-treatingarea comprising a first region including an abrading region configuredfor treating the first tissue type, a first inner surface of the wall inthe first region being a first distance from the central longitudinalaxis, said second tissue-treating area comprising a second regionincluding a cutting head window for treating the second tissue type,said cutting window communicating with said hollow interior portion ofsaid cutting head, said cutting head window being defined partially by apair of edges of said cutting head which are configured to cut tissueand are spaced peripherally from one another along said cutting head, asecond inner surface of the wall in the second region being a seconddistance from the central longitudinal axis, the second distance beinggreater than the first distance, said cutting head being disposed withinsaid distal end of said housing element axially adjacent said housingelement window such that said edges of said cutting head window aredisposed to create a scissoring action with said edges of said housingelement window to treat tissue located within said windows duringmovement of said cutting head relative to said housing element window.22. The surgical tool system of claim 21, wherein said edges of saidcutting head window are disposed radially adjacent to said edges of saidhousing element window.
 23. The surgical tool system of claim 21,wherein said abrading region of said first tissue-treating areacomprises a flute disposed in circumferentially adjacent relation with acutting surface, said flute and said cutting surface extendinglongitudinally along said cutting head either helically about thecentral longitudinal axis or linearly in substantially parallel relationwith the central longitudinal axis.
 24. The surgical tool system ofclaim 21, wherein the wall which defines said hollow interior portionand through which said cutting element window extends has a greaterthickness in an area corresponding to said first tissue-treating areathan a thickness of said wall at respective regions of said walldisposed closely adjacent said edges of said second tissue-treatingarea.
 25. The surgical tool system of claim 24, wherein said abradingregion of said first tissue-treating area includes a plurality ofalternating cutting surfaces and flutes, each said cutting surfacehaving a terminal outer edge, said wall of said cutting head defining aland immediately adjacent each said terminal outer edge, each said landhaving an outer diameter substantially similar to an inner diameter ofan inner surface disposed on said distal end of said housing element,each said land forming a bearing surface on said cutting head forcooperation with said inner surface of said housing element duringmovement of said cutting head relative thereto.
 26. The surgical toolsystem of claim 25, wherein one of said distal end of said housingelement or said cutting head comprises a material having a greaterhardness than a hardness of a material of the other of said distal endof said housing element and said cutting head.
 27. The surgical toolsystem of claim 21, wherein said abrading region of said firsttissue-treating area extends circumferentially along a substantialportion of said exterior portion of said cutting head and comprises asolid and non-windowed portion thereof which is not in communicationwith said hollow interior portion.
 28. The surgical tool system of claim21, wherein the first tissue-treating area and the secondtissue-treating area are spaced apart by a smooth surface of the cuttinghead.
 29. The surgical tool system of claim 28, wherein the firsttissue-treating area includes flutes and the second tissue-treating areaincludes teeth, the smooth surface separating the flutes and the teeth.30. The surgical tool system of claim 21, wherein the firsttissue-treating area includes a flute and a land adjacent to the flute,the flute being recessed relative to a rounded outer surface of thecutting head and the land being flush with the rounded outer surface ofthe cutting head.
 31. A method of treating tissue at a surgical site,the tissue at the surgical site being of a first tissue type having afirst hardness and a second tissue type having a second hardness lessthan the first hardness, said method comprising: treating the firsttissue type with an abrading region in a first region of a firsttissue-treating area provided on a cutting head of a single surgicalresection tool, the abrading region extending along a portion of a totalouter peripheral area of the cutting head; and treating the secondtissue type with a second region of a second tissue-treating areaprovided on the cutting head of the single surgical resection tool, thesecond tissue-treating area being circumferentially spaced from thefirst tissue-treating area, wherein the second tissue-treating areaincludes a window on the cutting head, the window having an asymmetricshape measured about a central longitudinal axis of the single surgicalresection tool, and wherein the cutting head includes a wall defining ahollow interior portion within said cutting head, a first inner surfaceof the wall in the first region being a first distance from the centrallongitudinal axis and a second inner surface of the wall in the secondregion being a second distance from the central longitudinal axis, thesecond distance being greater than the first distance.
 32. The method ofclaim 31, wherein the first tissue type comprises bone or cartilage or acombination thereof, and the second tissue type comprises ligaments,tendons or muscle or a combination thereof, and the treating of thefirst tissue type is performed subsequent to the treating of the secondtissue type.
 33. The method of claim 31, including operating the singlesurgical accessory in first and second opposite rotational directionswhen treating the second tissue type.
 34. The method of claim 33,wherein treating the second tissue type includes operating the singlesurgical accessory to cut the second tissue type with a first set ofteeth on a first side of the window and a second set of teeth on asecond side of the window opposite the first side, a quantity of teethin the first set of teeth being different than a quantity of teeth inthe second set of teeth.
 35. The method of claim 34, wherein teeth inthe first set of teeth have a first shape and teeth in the second set ofteeth have a second shape different from the first shape.
 36. The methodof claim 31, including operating the single surgical accessory in asingle rotational direction when treating the first tissue type.
 37. Themethod of claim 31, including operating the single surgical accessory infirst and second opposite rotational directions to treat the secondtissue type, and thereafter operating the single surgical accessory inthe first rotational direction to treat the first tissue type.